Stamping Dies Research Articles

Cooling Rate of Hot Stamping Dies by Constructed Cooling Temperature Trend Model

Cooling Rate of Hot Stamping Dies by Constructed Cooling Temperature Trend Model

In-process Monitoring during Stamping of Thin Plate: Propagation Characteristics of Ultrasonic Waves in Cylindrical Stamping Dies

In-process Monitoring during Stamping of Thin Plate: Propagation Characteristics of Ultrasonic Waves in Cylindrical Stamping Dies

Concurrent Engineering for Uppers Stream Process of Stamping Dies

The new-product development process is very important to manufacturing companies in all the product being developed. The product being developed must meet all internal company processes, customer requirement and to be delivered at the planned time. The modern approach in new product development is concurrent engineering. This paper reviews the concurrent engineering development and practices in several countries and industry. An investigation on concurrent engineering approach to selected manufacturing companies were conducted and analyzed. Concurrent engineering implementation is moderate due to organizational, tools and communication barriers. Secondly, the use of digital tools such as Electronic Data Management/Computer Aided Engineering/Computer Integrated Manufacturing is low. To ensure the success of concurrent engineering for critical process in new product development such as stamping process, the stamped part accuracy and considerable processing timings are the key factors.

Case Study to Illustrate the Potential of Conformal Cooling Channels for Hot Stamping Dies Manufactured Using Hybrid Process of Laser Metal Deposition (LMD) and Milling

Hot stamping dies include cooling channels to treat the formed sheet. The optimum cooling channels of dies and molds should adapt to the shape and surface of the dies, so that a homogeneous temperature distribution and cooling are guaranteed. Nevertheless, cooling ducts are conventionally manufactured by deep drilling, attaining straight channels unable to follow the geometry of the tool. Laser Metal Deposition (LMD) is an additive manufacturing technique capable of fabricating nearly free-form integrated cooling channels and therefore shape the so-called conformal cooling. The present work investigates the design and manufacturing of conformal cooling ducts, which are additively built up on hot work steel and then milled in order to attain the final part. Their mechanical performance and heat transfer capability has been evaluated, both experimentally and by means of thermal simulation. Finally, conformal cooling conduits are evaluated and compared to traditional straight channels. The results show that LMD is a proper technology for the generation of cooling ducts, opening the possibility to produce new geometries on dies and molds and, therefore, new products.

Tribological Behavior of Laser Textured Hot Stamping Dies

Hot stamping of high strength steels has been continuously developed in the automotive industry to improve mechanical properties and surface quality of stamped components. One of the main challenges faced by researchers and technicians is to improve stamping dies lifetime by reducing the wear caused by high pressures and temperatures present during the process. This paper analyzes the laser texturing of hot stamping dies and discusses how different surfaces textures influence the lubrication and wear mechanisms. To this purpose, experimental tests and numerical simulation were carried out to define the die region to be texturized and to characterize the textured surface topography before and after hot stamping tests with a 3D surface profilometer and scanning electron microscopy. Results showed that laser texturing influences the lubrication at the interface die-hot sheet and improves die lifetime. In this work, the best texture presented dimples with the highest diameter, depth, and spacing, with the surface topography and dimples morphology practically preserved after the hot stamping tests.

Optimal Design for Cooling System of Hot Stamping Dies

Optimal Design for Cooling System of Hot Stamping Dies

Tribological Properties of Coatings for Sheet Metal Stamping Dies

The conventional and innovative surface technologies are applied to sheet metal stamping dies in order to produce a composite material with properties unattainable in either the base or surface material. To select proper materials for forming dies the systematic evaluation of dies materials, their heat treatment and coatings are required. This paper deals with evaluation of plasma sprayed coatings Cr2O3, Al2O3 and WC12Co by pressure plate-ring test (tester T 05) and deep drawing process. Friction coefficients and seizure of these coatings were studied under dry and wet friction conditions. For different types of die rings (with and without ceramic coatings) the punching forces were measured during deep-drawing process. The results show that the main advantage of application of plasma sprayed coatings on the die contact surfaces under wet friction conditions compare to dies made of the tool steel may be the increase of seizure resistance of stamped part surface. The more significant difference in the friction coefficient values was not observed.

The use of Reverse Rngineering in the Design of New Stamping Dies

The use of Reverse Rngineering in the Design of New Stamping Dies

A Study on the Method for Punching Small Holes with Cold Stamping Dies

this paper first determines the deformation modes of punching small-hole punches by analyzing the forms of the stress applied to die working parts. It analyzes the disadvantages of existing methods for preventing the buckling problem in punching small holes such as protective jackets and proposes a method for preventing the buckling of punches by reducing the punching force so as to make it possible to punch smaller holes.

面向激光强化工艺的冲压模具表面应力的计算方法

面向激光强化工艺的冲压模具表面应力的计算方法

面向激光强化工艺的冲压模具表面应力的计算方法

面向激光强化工艺的冲压模具表面应力的计算方法

Application of Innovative PVD Coating to Stamping Dies for Processing Ultra-High Tensile Strength Steel Sheets

Application of Innovative PVD Coating to Stamping Dies for Processing Ultra-High Tensile Strength Steel Sheets

Robot Grinding and Finishing of Cast Iron Stamping Dies

This paper describes a method for finishing cast iron stamping dies. The task is to remove tool marks in the form of grooves and cusps left by a ball-end milling tool. The bottoms of the grooves represent the desired final surface profile. The method consists of using a closed-loop force-controlled robot with a flexible grinding disk coupled to a means for measuring the height of the partially ground cusps. Measurement is particularly easy, accurate, and sensitive if the tops of the partially ground cusps are flat, a condition that is not easy to obtain; otherwise accurate measurement is a chore. The Taguchi method is used to determine process parameters (grinding grit size, feed speed, disk speed, disk inclination angle, etc.) that yield flat tops. This grinding strategy has proven successful. A smooth, regular, and accurate final shape is obtained in spite of the relatively poor position accuracy of the robot. The measurement strategy has not been implemented yet but it appears feasible based on preliminary experiments.