AA Seminor Under Special Study

ON“ Analysis of Hot Isothermal Copper Extrusion for Multi-

Channel” Submitted in partial fulfillment of the requirement for the award of degree of

MASTER OF TECHNOLOGYIN

Mechanical Engineering Department(Production & Industrial Engineering)

BY Brijesh Kumar Patel

(14MTMEPIE011)Submitted to

Er. Raul Davis

SHEPHEARD SCHOOLOF ENGINEERING AND TECHNOLOGYSAM HIGGINBOTTOM INSTITUTE OF AGRICULTURE,

TECHNOLOGY AND SCIENCESDeemed-to-be-University

(FORMERLY ALLAHABAD AGRICULTURAL INSTITUTE)NAINI, ALLAHABAD-211007

Extrusion ProcessA compression forming process in which the work metal is forced to flow through a die opening to produce a desired cross-sectional shape.

Example of Extrusion Parts

Railings for Sliding Doors

Window Frames

Aluminum Ladders

Extrusions can be cut into desired

lengths, allowing for discreet parts such to

be produced as Gears, and Brackets

Multi Channel ProfileResearch focused on extrusion of two multi-

channel tube profile of different ratio. One tube is 11- channel profile and the other a 2- channel design.

Fig 1. 2- Channel profile Fig2. 11 – Channel Profile

By these process 2-channel and multi channel product are produced which are shown in fig. The temperature are required for the copper extrusion is 750 oC to 900 oC.

Fig (1) 2- channel Product Fig (2)11- channel Product

Extrusion ProcessHot extrusion :

Keeping the processing temperature to above the re-crystalline temperature. Reducing the ram force, increasing the ram speed, and reduction of grain flow characteristics. Controlling the cooling is a problem. Glass may be used as a lubricant.

Cold extrusion :Often used to produce discrete parts. Increase strength due to strain hardening, close tolerances, improved surface finish, absence of oxide layer and high production rates.

Types of Extrusion1.Direct Extrusion

The ram forces the work billet metal to move forward to pass through the die opening.

Friction increases the extrusion force.

Types of ExtrusionIndirect Extrusion:Metal is forced to flow through the die in an opposite direction to the ram’s motion.

Lower extrusion force as the work billet metal is not moving relative to the container wall.

Hydrostatic ExtrusionThe chamber, which is larger than the billet, is

filled with a fluid. The fluid is compressed with the ram and pushes the billet forward.

Benefit: no friction to overcome along sides of chamber.

Die DesignMain types of die designs:

1) Square dies: Used in extruding nonferrous metals- Develops dead metal zones that form the

dies angle2) Solid or Hollow Dies: Used in extruding tubing

products- The ram is fitted with a mandrel that pierces a hole in the billet-Wall thickness is limited to 1 mm for aluminum. 3mm for stainless steels, 5mm to stainless steels

Die MaterialsHot Worked dies Steels

are used for hot extrusion

Coatings such as zirconia used to extend die life• Not suitable for dies

used for complex shapes because of the sever stress gradients that develop in the die.

Lubricants Lubrication Is important in hot extrusions

because of major effects on:a) Material flowb) Surface finish on extrusionc) Product qualityd) Extrusion forces

Metal flow

- A common technique in investigating a flow is to section the round billet in half

- Dead-Metal Zone – The corner of the material stays stationary. Bright finishes result due to material flowing past the die angle

- Fig a – flow patterns attained with low friction- Fig b – flow patterns attained with high friction- Fig c – flow pattern attained with high friction or cooling of the

billets outer regions in the chamber

Extrusion Defects

a) Centre-burst: internal crack due to excessive tensile stress at the centre possibly because of high die angle, low extrusion ratio.

b) Piping: sink hole at the end of billet under direct extrusion.

c) Surface cracking: High part temperature due to low extrusion speed and high strain rates.

Extrusion Analysis

Extrusion ratio =

MaterialsCommon metals used in extraction

process:AluminumCopperSteelsStainless steelsMagnesiumLead

Advantage of Cold & Hot ExtrusionCold Extrusion:

Better mechanical properties due to work-hardening.

Good dimensional tolerances & surface finish.No need to heat billet.Competitive production rates & costs.

Hot Extrusion:Larger variety of materials.Less forces required.Better material flow.

Referances [1] Bauser, M., Sauer, G., and Siegert, K. (2006). Extrusion. Materials Park, OH: ASM

International. pp. 203-241, pp. 544-545. [2] International Copper Association. (2012). Semi-finished antimicrobial copper products.

Retrieved from http://www.antimicrobialcopper.com/uk/find-products-andpartners/ find-antimicrobial-copper-semi-finished-products.aspx

[3] (n.d.). Direct extrusion.[Web Drawing]. Retrieved from http://www.roymech.co.uk/Useful_Tables/Manufacturing/Extruding.html

[4] Kraft, F. (2011). “Extrusion of thin-wall multi-channel copper profiles”, presented at Materials Science & Technology 2011 Conference and Exhibition sponsored by ACERS,AIST, ASM, TMS and NACE.

[5] Kraft, F. (2011). Apparatus and Method for Extruding Micro-Channel Tubes, European Patent, number 2104577, August 3, 2011.

[6] Vaitkus, V. (2008). A process for the direct hot extrusion of hollow copper profiles. (Master's thesis, Ohio University). pp. 13-24, pp. 48-62.

[7] Kraft, F. (2012) Micro-Channel Tubes and Apparatus and Method for Forming Micro-Channel Tubes. U.S. Patent, number 8191393 B2, June 5, 2012.

[8] ATI All vac. “ATI 720 alloy".(n.d.). Retrieved from http://www.alleghenytechnologies.com/aerospace/docs/aerospacedatasheets/ATI7Nickel.pdf

Thanking You