lecture slides - philadelphia university · 2016. 10. 26. · adhesive joint design guidelines...
TRANSCRIPT
![Page 1: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/1.jpg)
Chapter 9
Welding, Bonding, and the
Design of Permanent Joints
Lecture Slides
The McGraw-Hill Companies © 2012
![Page 2: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/2.jpg)
Chapter Outline
Shigley’s Mechanical Engineering Design
![Page 3: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/3.jpg)
Welding Symbols
Welding symbol standardized by American Welding Society
Specifies details of weld on machine drawings
Shigley’s Mechanical Engineering Design
Fig. 9–4
![Page 4: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/4.jpg)
Welding Symbols
Shigley’s Mechanical Engineering Design
Fig. 9–1
![Page 5: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/5.jpg)
Welding Symbols
Arrow side of a joint is the line, side, area, or near member to
which the arrow points
The side opposite the arrow side is the other side
Shape of weld is shown with the symbols below
Shigley’s Mechanical Engineering Design
Fig. 9–2
![Page 6: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/6.jpg)
Welding Symbol Examples
Shigley’s Mechanical Engineering Design
Weld leg size of 5 mm
Fillet weld
Both sides
Intermittent and
staggered 60 mm along
on 200 mm centers
Leg size of 5 mm
On one side only
(outside)
Circle indicates all the
way around
![Page 7: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/7.jpg)
Welding Symbol Examples
Shigley’s Mechanical Engineering Design
Fig. 9–5
![Page 8: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/8.jpg)
Welding Symbol Examples
Shigley’s Mechanical Engineering Design
Fig. 9–6
![Page 9: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/9.jpg)
Tensile Butt Joint
Simple butt joint loaded in tension or compression
Stress is normal stress
Throat h does not include extra reinforcement
Reinforcement adds some strength for static loaded joints
Reinforcement adds stress concentration and should be ground
off for fatigue loaded joints
Shigley’s Mechanical Engineering Design Fig. 9–7a
![Page 10: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/10.jpg)
Shear Butt Joint
Simple butt joint loaded in shear
Average shear stress
Shigley’s Mechanical Engineering Design
Fig. 9–7b
![Page 11: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/11.jpg)
Transverse Fillet Weld
Joint loaded in tension
Weld loading is complex
Shigley’s Mechanical Engineering Design
Fig. 9–8
Fig. 9–9
![Page 12: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/12.jpg)
Transverse Fillet Weld
Summation of forces
Law of sines
Solving for throat thickness t
Shigley’s Mechanical Engineering Design
Fig. 9–9
![Page 13: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/13.jpg)
Transverse Fillet Weld
Nominal stresses at angle q
Von Mises Stress at angle q
Shigley’s Mechanical Engineering Design
Fig. 9–9
![Page 14: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/14.jpg)
Transverse Fillet Weld
Largest von Mises stress occurs at q = 62.5º with value of
s' = 2.16F/(hl)
Maximum shear stress occurs at q = 67.5º with value of
tmax = 1.207F/(hl)
Shigley’s Mechanical Engineering Design
Fig. 9–9
![Page 15: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/15.jpg)
Experimental Stresses in Transverse Fillet Weld
Experimental results are more complex
Shigley’s Mechanical Engineering Design
Fig. 9–10
![Page 16: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/16.jpg)
Transverse Fillet Weld Simplified Model
No analytical approach accurately predicts the experimentally
measured stresses.
Standard practice is to use a simple and conservative model
Assume the external load is carried entirely by shear forces on
the minimum throat area.
By ignoring normal stress on throat, the shearing stresses are
inflated sufficiently to render the model conservative.
By comparison with previous maximum shear stress model, this
inflates estimated shear stress by factor of 1.414/1.207 = 1.17.
Shigley’s Mechanical Engineering Design
![Page 17: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/17.jpg)
Parallel Fillet Welds
Same equation also applies for simpler case of simple shear
loading in fillet weld
Shigley’s Mechanical Engineering Design
Fig. 9–11
![Page 18: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/18.jpg)
Fillet Welds Loaded in Torsion
Fillet welds carrying both direct shear V and moment M
Primary shear
Secondary shear
A is the throat area of all welds
r is distance from centroid of weld group to point of interest
J is second polar moment of area of weld group about centroid of group
Shigley’s Mechanical Engineering Design
Fig. 9–12
![Page 19: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/19.jpg)
Example of Finding A and J
Rectangles represent
throat areas. t = 0.707 h
Shigley’s Mechanical Engineering Design
Fig. 9–13
![Page 20: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/20.jpg)
Example of Finding A and J
Note that t3 terms will be
very small compared to
b3 and d3
Usually neglected
Leaves JG1 and JG2 linear
in weld width
Can normalize by
treating each weld as a
line with unit thickness t
Results in unit second
polar moment of area, Ju
Since t = 0.707h,
J = 0.707hJu
Shigley’s Mechanical Engineering Design
Fig. 9–13
![Page 21: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/21.jpg)
Common Torsional Properties of Fillet Welds (Table 9–1)
Shigley’s Mechanical Engineering Design
![Page 22: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/22.jpg)
Common Torsional Properties of Fillet Welds (Table 9–1)
Shigley’s Mechanical Engineering Design
![Page 23: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/23.jpg)
Example 9–1
Shigley’s Mechanical Engineering Design
Fig. 9–14
![Page 24: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/24.jpg)
Example 9–1
Shigley’s Mechanical Engineering Design
Fig. 9–15
![Page 25: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/25.jpg)
Example 9–1
Shigley’s Mechanical Engineering Design
Fig. 9–15
![Page 26: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/26.jpg)
Example 9–1
Shigley’s Mechanical Engineering Design
Fig. 9–15
![Page 27: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/27.jpg)
Example 9–1
Shigley’s Mechanical Engineering Design
![Page 28: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/28.jpg)
Example 9–1
Shigley’s Mechanical Engineering Design
Fig. 9–16
![Page 29: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/29.jpg)
Example 9–1
Shigley’s Mechanical Engineering Design Fig. 9–16
![Page 30: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/30.jpg)
Fillet Welds Loaded in Bending
Fillet welds carry both shear V and moment M
Shigley’s Mechanical Engineering Design
Fig. 9–17
![Page 31: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/31.jpg)
Bending Properties of Fillet Welds (Table 9–2)
Shigley’s Mechanical Engineering Design
![Page 32: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/32.jpg)
Bending Properties of Fillet Welds (Table 9–2)
Shigley’s Mechanical Engineering Design
![Page 33: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/33.jpg)
Strength of Welded Joints
Must check for failure in parent material and in weld
Weld strength is dependent on choice of electrode material
Weld material is often stronger than parent material
Parent material experiences heat treatment near weld
Cold drawn parent material may become more like hot rolled in
vicinity of weld
Often welded joints are designed by following codes rather than
designing by the conventional factor of safety method
Shigley’s Mechanical Engineering Design
![Page 34: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/34.jpg)
Minimum Weld-Metal Properties (Table 9–3)
Shigley’s Mechanical Engineering Design
![Page 35: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/35.jpg)
Stresses Permitted by the AISC Code for Weld Metal
Shigley’s Mechanical Engineering Design
Table 9–4
![Page 36: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/36.jpg)
Fatigue Stress-Concentration Factors
Kfs appropriate for application to shear stresses
Use for parent metal and for weld metal
Shigley’s Mechanical Engineering Design
![Page 37: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/37.jpg)
Allowable Load or Various Sizes of Fillet Welds (Table 9–6)
Shigley’s Mechanical Engineering Design
![Page 38: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/38.jpg)
Minimum Fillet Weld Size, h (Table 9–6)
Shigley’s Mechanical Engineering Design
![Page 39: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/39.jpg)
Example 9–2
Shigley’s Mechanical Engineering Design
Fig. 9–18
![Page 40: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/40.jpg)
Example 9–2
Shigley’s Mechanical Engineering Design
![Page 41: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/41.jpg)
Example 9–2
Shigley’s Mechanical Engineering Design
![Page 42: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/42.jpg)
Example 9–3
Shigley’s Mechanical Engineering Design
Fig. 9–19
![Page 43: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/43.jpg)
Example 9–3
Shigley’s Mechanical Engineering Design
![Page 44: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/44.jpg)
Example 9–3
Shigley’s Mechanical Engineering Design
![Page 45: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/45.jpg)
Example 9–3
Shigley’s Mechanical Engineering Design
![Page 46: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/46.jpg)
Example 9–3
Shigley’s Mechanical Engineering Design
![Page 47: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/47.jpg)
Example 9–3
Shigley’s Mechanical Engineering Design
![Page 48: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/48.jpg)
Example 9–4
Shigley’s Mechanical Engineering Design
Fig. 9–20
![Page 49: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/49.jpg)
Example 9–4
Shigley’s Mechanical Engineering Design
![Page 50: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/50.jpg)
Example 9–4
Shigley’s Mechanical Engineering Design
![Page 51: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/51.jpg)
Example 9–4
Shigley’s Mechanical Engineering Design
![Page 52: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/52.jpg)
Example 9–5
Shigley’s Mechanical Engineering Design
Fig. 9–21
![Page 53: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/53.jpg)
Example 9–5
Shigley’s Mechanical Engineering Design
![Page 54: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/54.jpg)
Example 9–5
Shigley’s Mechanical Engineering Design
![Page 55: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/55.jpg)
Example 9–6
Shigley’s Mechanical Engineering Design
Fig. 9–22
![Page 56: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/56.jpg)
Example 9–6
Shigley’s Mechanical Engineering Design
![Page 57: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/57.jpg)
Example 9–6
Shigley’s Mechanical Engineering Design
![Page 58: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/58.jpg)
Resistance Welding
Welding by passing an electric current through parts that are
pressed together
Common forms are spot welding and seam welding
Failure by shear of weld or tearing of member
Avoid loading joint in tension to avoid tearing
Shigley’s Mechanical Engineering Design Fig. 9–23
![Page 59: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/59.jpg)
Adhesive Bonding
Adhesive bonding has unique advantages
Reduced weight, sealing capabilities, reduced part count, reduced
assembly time, improved fatigue and corrosion resistance, reduced
stress concentration associated with bolt holes
Shigley’s Mechanical Engineering Design
Fig. 9–24
![Page 60: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/60.jpg)
Types of Adhesives
May be classified by
◦ Chemistry
Epoxies, polyurethanes, polyimides
◦ Form
Paste, liquid, film, pellets, tape
◦ Type
Hot melt, reactive hot melt, thermosetting, pressure sensitive,
contact
◦ Load-carrying capability
Structural, semi-structural, non-structural
Shigley’s Mechanical Engineering Design
![Page 61: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/61.jpg)
Mechanical Performance of Various Types of Adhesives
Shigley’s Mechanical Engineering Design
Table 9–7
![Page 62: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/62.jpg)
Stress Distributions
Adhesive joints are much stronger
in shear loading than tensile loading
Lap-shear joints are important for
test specimens and for practical
designs
Simplest analysis assumes uniform
stress distribution over bonded area
Most joints actually experience
significant peaks of stress
Shigley’s Mechanical Engineering Design Fig. 9–25
![Page 63: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/63.jpg)
Double-lap Joint
Classic analysis of double-lap joint known as shear-lag model
Double joint eliminates complication of bending from
eccentricity
Shigley’s Mechanical Engineering Design Fig. 9–26
![Page 64: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/64.jpg)
Double-lap Joint
Shear-stress distribution is given by
Shigley’s Mechanical Engineering Design Fig. 9–26b
![Page 65: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/65.jpg)
Example 9–7
Shigley’s Mechanical Engineering Design
Fig. 9–26
![Page 66: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/66.jpg)
Example 9–7
Shigley’s Mechanical Engineering Design
![Page 67: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/67.jpg)
Example 9–7
Shigley’s Mechanical Engineering Design
Fig. 9–27
![Page 68: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/68.jpg)
Example 9-7
Shigley’s Mechanical Engineering Design
![Page 69: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/69.jpg)
Example 9-7
Shigley’s Mechanical Engineering Design
![Page 70: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/70.jpg)
Single-lap Joint
Eccentricity introduces bending
Bending can as much as double the resulting shear stresses
Near ends of joint peel stresses can be large, causing joint failure
Shigley’s Mechanical Engineering Design Fig. 9–28
![Page 71: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/71.jpg)
Single-lap Joint
Shear and peal stresses in single-lap joint, as calculated by Goland
and Reissner
Volkersen curve is for double-lap joint
Shigley’s Mechanical Engineering Design Fig. 9–28
![Page 72: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/72.jpg)
Adhesive Joint Design Guidelines
Design to place bondline in shear, not peel.
Use adhesives with adequate ductility to reduce stress
concentrations and increase toughness to resist debond
propagation.
Recognize environmental limitations of adhesives and surface
preparation.
Design to facilitate inspection.
Allow sufficient bond area to tolerate some debonding before
becoming critical.
Attempt to bond to multiple surfaces to support loads in any
direction.
Consider using adhesives in conjunction with spot welds, rivets, or
bolts.
Shigley’s Mechanical Engineering Design
![Page 73: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/73.jpg)
Design Ideas for Improved Bonding
Shigley’s Mechanical Engineering Design Fig. 9–29
![Page 74: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/74.jpg)
Design Ideas for Improved Bonding
Shigley’s Mechanical Engineering Design Fig. 9–29
![Page 75: Lecture Slides - Philadelphia University · 2016. 10. 26. · Adhesive Joint Design Guidelines Design to place bondline in shear, not peel. Use adhesives with adequate ductility to](https://reader035.vdocuments.us/reader035/viewer/2022071405/60f9b1c39e46166d9e244d66/html5/thumbnails/75.jpg)
Design Ideas for Improved Bonding
Shigley’s Mechanical Engineering Design Fig. 9–29