June 13, 2017

The Main Reasons for The Burst of Metal Precision Stamping Die

Because of different stamping process and different working conditions, the cause of precision stamping die burst can be in many ways. The following aspects of comprehensive analysis of the cause of mold burst:

1. The stamping die with bad raw material will broken in the subsequent processing.The life of molds with different materials is often different. To this end, two basic requirements are put forward for the working parts of dies:

– 1.1 The properties of the material should be with high hardness, high strength, high wear resistance and sufficient toughness, heat treatment deformation, and some hot hardness.

– 1.2 Good process performance. Die working parts manufacturing process is relatively complex. We must have all kinds of processing adaptability, such as ductility, machinability, hardenability and hardenability, quenching crack sensitivity and grindability. Selecting the die material with excellent performance usually based on the material properties, stamping production quantity and precision requirements. At same time,the technology and economy are the index.

 

2. Heat treatment: Deformation caused by improper quenching and tempering process. Practice shows that thermal processing quality of mold greatly influence mold performance and life time. From the analysis of the causes of die failure, we can know that quenching deformation and cracking of the working mold parts and the early fracture in the use process are all related to molds’ heat treatment process.

– 2.1 Forging process:An important part of precision stamping die working parts manufacturing process. for mold high alloy tool steel, forging temperature range should be strictly controlled through making correct heating specification, using the correct method of forging process and slow cooling after forging or annealing timely.

– 2.2 Preliminary heat treatment: According to different material, stamping die parts were manufactured through annealing and normalizing pre-heat treatment process.It can improve the organization, eliminate the defects of forging blank and improve the machining process. High carbon alloy steel after appropriate prepare heat treatment can eliminate mesh two cementite or chain carbides. Carbide will be spheroidizing and refinement to promote the carbide distribution uniformity. It helps to ensure the quenching, tempering quality and to improve the service life of the die.

 

3.The grinding of precision stamping dies is not flat enough to produce deflection
The surface quality of the mold working parts is closely related the superiority of the dies’ wear resistance, fracture resistance and anti adhesion ability. It directly affect the tolling life time. Especially the surface roughness has great influence on stamping die life time. If the surface roughness value is too large, it will cause the phenomenon of stress concentration on working, cracks at its peak and valley, influence dies’ durability and affect the corrosion resistance of the workpiece surface. In that way, precision stamping die’ life time and accuracy will be directly affected.