The materials for manufacturing stamping dies include steel, cemented carbide, steel bonded cemented carbide, zinc based alloy, low melting point alloy, aluminum bronze, polymer materials, etc.
At present, most of the materials used for manufacturing stamping dies are mainly steel.
The commonly used types of materials for working parts of dies include: carbon tool steel, low alloy tool steel, high-carbon high chromium or medium chromium tool steel, medium carbon alloy steel, high-speed steel, base steel, hard alloy, steel-bonded hard alloy, etc.
Details are as follows:
1. Carbon tool steel
T8A, T10A and other carbon tool steels are widely used in molds, which have the advantages of good processing performance and low price.
However, the hardenability and red hardness are poor, the deformation after heat treatment is large, and the bearing capacity is low.
2. Low alloy tool steel
Low alloy tool steel is a kind of carbon tool steel with proper alloying elements added.
Compared with carbon tool steel, it reduces quenching deformation and cracking tendency, improves the hardenability of the steel, and has better wear resistance.
The low-alloy steels used for mold manufacturing include CrWMn, 9Mn2V, 7CrSiMnMoV (code CH-1), 6CrNiSiMnMoV (code GD), etc.
3. High carbon and high chromium tool steel
The commonly used high carbon and high chromium tool steels are Cr12, Cr12MoV and Cr12Mo1V1 (code D2).
They have good hardenability, hardenability and wear resistance, and have little deformation after heat treatment.
They are high wear-resistant and micro deformation die steels, with bearing capacity second only to high-speed steel.
However, carbide segregation is serious, so repeated upsetting and drawing (axial upsetting and radial drawing) must be carried out to reduce the nonuniformity of carbide and improve the service performance.
4. High carbon medium chromium tool steel
High carbon and medium chromium tool steels used for molds include Cr4W2MoV, Cr6WV, Cr5MoV, etc.
They have low chromium content, less eutectic carbides, uniform carbides distribution, small heat treatment deformation, good hardenability and dimensional stability.
Compared with the high carbon and high chromium steel with relatively serious carbide segregation, the properties of the steel are improved.
5. High speed steel
High speed steel has the highest hardness, wear resistance and compressive strength among die steels, and its bearing capacity is very high.
W18Cr4V (code 8-4-1) and W6Mo5Cr4V2 (code 6-5-4-2, American brand M2) with less tungsten are commonly used in the mold, as well as the carbon and vanadium reduction high speed steel 6W6Mo5Cr4V (code 6W6 or low carbon M2) developed to improve toughness.
High speed steel also needs to be forged to improve its carbide distribution.
6. Base steel
A small amount of other elements are added to the basic composition of high-speed steel, and the carbon content is appropriately increased or decreased to improve the properties of the steel.
Such steels are collectively referred to as base steels.
They not only have the characteristics of high-speed steel, have certain wear resistance and hardness, but also have better fatigue strength and toughness than high-speed steel.
They are cold working die steels with high strength and toughness, but their material costs are lower than high-speed steel.
The base steels commonly used in the die include 6Cr4W3Mo2VNb (code 65Nb), 7Cr7Mo2V2Si (code LD), 5Cr4Mo3SiMnVAL (code 012AL), etc.
7. Hardmetals and steel bonded Hardmetals
The hardness and wear resistance of cemented carbide are higher than that of any other kind of die steel, but the bending strength and toughness are poor.
The cemented carbide used as the mold is tungsten cobalt.
For the mold with low impact and high wear resistance, the cemented carbide with low cobalt content can be selected.
Cemented carbide with high cobalt content can be selected for the die with high impact.
8. Steel bonded cemented carbide
Steel bonded cemented carbide is sintered by powder metallurgy with iron powder added with a small amount of alloy element powder (such as chromium, molybdenum, tungsten, vanadium, etc.) as binder, titanium carbide or tungsten carbide as hard phase.
The matrix of steel bonded cemented carbide is steel, which overcomes the shortcomings of poor toughness and difficult processing of cemented carbide, and can be cut, welded, forged and heat treated.
Steel bonded cemented carbides contain a large amount of carbides.
Although their hardness and wear resistance are lower than those of cemented carbides, they are still higher than other steels.
After quenching and tempering, the hardness can reach 68 ~ 73 HRC.
What are soft and hard materials in the press tool?
In the stamping die, it refers to die steel with a hardness of about HRC35 and a relatively low hardness, such as 45 # steel, A3, Q235, etc.
If you knock something with a little higher hardness on it, you can get a hole.
This material is very soft, so it is used to be called “soft material” because of its good seismic performance.
It is generally used to make upper and lower support plates, upper and lower pads and upper and lower mold bases of stamping dies.
In the stamping die, it refers to the die steel materials with hardness (after heat treatment) of about HRC 58 ~ 62 or above, such as Cr12, Cr12Mo1V1, Cr12MoV, Skd-51, Skd-11, W6Mo5Cr4V2 (tungsten steel).
These steel materials have high hardness (but are also brittle, and may be broken by you if you don’t pay attention to them, 55).
They are generally used for the blade, punch or other parts requiring high hardness of the stamping die.