latest improvements for hot forming dies and technologies · latest improvements for hot forming...
TRANSCRIPT
Tooling
Latest improvements for hot forming
dies and technologies
Techtank Conference 2017
Olofström - Sweden
Jose Miguel Martin
Tooling
SUMMARY
1. Company introduction
2. Multi properties solutions
3. Cutting solutions for process improvements
4. Hot forming technologies for other materials
Tooling
COMPANY INTRODUCTION
Hotteknik: Business Unit for
Hot Forming Technology
Tooling
COMPANY INTRODUCTION
Tooling
COMPANY INTRODUCTION
TOTAL 284 M€
174 M€ 97 M€
13 M€
Turnover
AutomotiveSystems
Energy
Stamping Dies
74%
22%
1% 3%
Workforce
AutomotiveSystemsStamping Dies
Energy
Group Services
AVERAGE 1.600
Tooling
COMPANY INTRODUCTION
Hot forming:
Tooling
COMPANY INTRODUCTION
Tooling
Optimizing mechanical properties and thickness of the part for saving weight and
improving crash performance.
Multi Properties parts solutions:
Different engineering solutions to improve car crash performance.
MULTI PROPERTIES SOLUTIONS
Tooling
Tailor quenched parts:
Different microstructures(properties) can be achieved by controlling the cooling
rate.
Tailor quenched considerations:
• To have good contact in die due to material dilatation.
• To get good geometrical and mechanical properties part.
• Different tool steels tested.
• Study low thermal conductivity steels capability for tailor tempering.
• Different temperature ranges influence in final properties.
• Insulation solution between different areas.
• Final part geometry compensation (Springback).
Technically supported by:
MULTI PROPERTIES SOLUTIONS
Tooling
Conclusions:
• Low conductivity materials have slight influence.
• The principal driver is the temperature of the steel block.
• Depending on final mechanical properties, tool temperature must be adjusted (Up to
450ºC-500ºC for 220-250 HV)
• Tool expansion and springback must be compensated to achieve a good final
geometrical accuracy
• Air gaps between blocks assure a good insulation between hot and cold areas
• Transition areas can be achieved between 30-40 mm.
* Simulation part dimensional measurements * Experimental part measurements
MULTI PROPERTIES SOLUTIONS
Tooling
Alternative to compensate tool expansion (Tailor Tempering)
1. Compensate the expansion of the heated steel blocks by analytical calculations or
simulations
2. Milling heated steel blocks at production temperature.
Considerations for milling at production temperature:
• Cooled milling head
• Milling head sensorized
• Heated steel block sensorized
• Thermographic camera for thermal measuring
• Photogrammetry for geometrical measurement
Technically supported by:
MULTI PROPERTIES SOLUTIONS
Tooling
Pre developed blank solution:
• Some areas are not laser cut after forming in order to reduce process cost.
• In areas where the trimming tolerances range allow it.
• Part process feasibility must allow work with pre developed solution.
Pre developed blank shape considerations:
• Analysis of areas and tolerances with pre developed blank
• Accurate centering systems for repeatability of process.
• Several blank shape iterations.
• Adjustment of parameters in simulation to reduce blank shape iterations.
Conclusions:
• Implemented solution in several produccion dies.
Project: JLR
CUTTING SOLUTIONS FOR PROCESS IMPROVEMENTS
Tooling
Hot Piercing solution:
• Some holes can be pierced in the forming operation to reduce cost.
• Implemented when part holes tolerances are reduced (location holes).
Hot Piercing considerations:
• Die design (Cooling channels, Cutting tools and scrapping)
• Cutting process parameters (Clearance, Sharp edge, Cutting temperature…)
• Tool steel, heat treatment and coatings selection in active parts .
• Cutting effort and thermal hole dilatation compensation.
Conclusions:
• Process cost can be reduced.
• Higher die manufacturing complexity.
• Lower cutting effort due to blank temperature.
CUTTING SOLUTIONS FOR PROCESS IMPROVEMENTS
Technically supported by:
Tooling
Hard Cutting solution:
• Some customers allow hard cutting process.
• Depending on project volume this process can be competitive.
Hard Cutting considerations:
• Tool steel selection in active parts.
• Optimization cutting parameters (angles, clearances, sharp …)
• Tool Stiffness (clearance variation during cut process)
• Optimization Heat treatment and coatings.
• Sock absorber is needed (press or die)
Project: FIAT
CUTTING SOLUTIONS FOR PROCESS IMPROVEMENTS
Tooling
Conclusions:
• Tool stress can be calculated by simulation (FEM).
• Tool stress is dependent on punching clearance and cutting edge radius.
• The reaction force is calculated and this value must be used for a correct die design to
prevent excessive tool displacement during the trim operation.
• Lower stress with optimal radius in the cutting edge.
• Process cost can be reduced.
• Higher dies investment
CUTTING SOLUTIONS FOR PROCESS IMPROVEMENTS
Tooling
MATERIAL TESTED:
Automotive
Aluminum:
- AA 5083
- AA 5754
- AA 6082
- AA 7075
Magnesium:
- AZ 31
HS Aluminum and Magnesium
• Formability for these materials is poor at room temperature.
• Hot stamping processes can improve their formability.
Technically supported by:
HOT FORMING TECHNOLOGIES FOR OTHER MATERIALS
Tooling
Batz font. 14 pts. Name Surname
[email protected] THANKS FOR YOUR ATTENTION
Jose Miguel Martin
Hot Forming Key Account Manager