Inspection Method of Stamping Parts Hardness

Stamping hardness testing using Rockwell hardness tester . Of small, having a complicated shape stampings can be used to test surface is small , not a common desktop on the Rockwell hardness testing. PHP Series Portable Superficial Rockwell hardness tester is suitable for testing the hardness of these stampings which is during the steel drum manuafacturing equipment.

Stamping metal processing, machinery manufacturing the most commonly used parts. Die stamping parts processing is the use of the metal strip forming separation occurs or processing methods. Very broad range of applications .

Stamping parts processing , including punching , bending , deep drawing, forming, finishing and other processes. Stamping parts processing materials are mainly hot-rolled or cold-rolled ( cold-rolled -based ) of the metal strip material , such as carbon steel , alloy steel plates, spring steel, galvanized sheet, tin plate, stainless steel , copper and copper alloys plates, aluminum and aluminum panels.

Hardness testing of metallic materials in the stamping process has a very important significance. Stamping industry, hardness testing can be divided into the following three parts:

1, the raw materials into the factory testing.

2 , the mold hardness testing.

3 , stamping parts stamping intermediate products and finished hardness testing.

Respectively, are presented below :

1 , stampings material hardness testing
Stamping hardness testing, its main purpose is to determine the extent of purchase sheet metal annealing suitability to be carried out subsequently stamping parts processing , different types of stamping process , requiring different levels of hardness plate .

Hot-rolled steel sheet is usually thick , steel standards with the general provisions to detect hardness Brinell hardness . Rockwell hardness testing hot-rolled steel is feasible, can be used HRB scale . Portable Rockwell hardness tester for testing hot rolled steel plate , you can not be tested under the conditions of the sampling , the operation is very simple.

Variety for cold rolled steel stamping parts processing mainly used to detect Rockwell hardness scales HRB usually , harder with HRC scale . Sheet material can be used Webster hardness tester can also be used surface Rockwell hardness scale HRN or HRT .

For stamping parts machining brass hardness can use the HRB Rockwell hardness scale testing. Softer brass and copper plate using HRF ruler . Thin gauge sheet metal using HRT .

For stamping parts machining aluminum plates available Webster Hardness testing, material thickness greater than 13mm can use bar hardness , low hardness of pure aluminum or aluminum alloy plate should be used to bar hardness .

For a variety of metal stamping parts processing can be used very thin plate surface Rockwell hardness scale and with the diamond point HR30T anvil in this way test HR30Tm hardness value. Test sheet thickness can be less than 0.05mm. This test method is the national standard GB / T 230.1-2004 is specified in Appendix A . You can also use surface Rockwell hardness HR15T and HR45T ruler , converted into HR30Tm after testing the hardness values.

Shenyang Star company's PHR Series Portable Rockwell / Superficial Rockwell hardness tester can sell the material warehouse or field use , the plates on the factory inspection need not sampled. It can be the raw material procurement stage testing before the move .You can carry the equipment to the steel plant or steel market to buy materials, confirm plate hardness meet the requirements before purchasing .

2 , stamping mold hardness testing
Die stamping die steel is the main material ( including tool steel and high speed steel ) , sometimes used carbide .

Stamping dies generally requires a high hardness and wear resistance, heat is essential.

Mold steel hardness testing mainly Rockwell hardness test HRC hardness value. When the mold is large, can be inconvenient when moving in the hardness . Carbide hardness testing using Rockwell hardness HRA scale .

In order to obtain high surface hardness and wear resistance , many stamping dies and stamping mold parts surface treatment should be carried out , for example, surface nitriding . For such people are very concerned about its mold surface hardness and hardened layer depth. For the volume is not too large , easy to move stamping dies , can be directly on the surface Rockwell hardness test on its surface hardness HRN values.Bulky, difficult to move the sample had to use cutting measures , after sampling the surface Rockwell hardness test on HRN values. You can also use the Vickers hardness test HV values. Another approach is to use small pieces of test pieces made ​​of the same material , heat treatment under the same conditions , and measure the hardness of the test piece , in order to estimate the hardness of stamping dies .

The company produces PHR Series Portable Superficial Rockwell hardness tester can be used for part of the small stamping mold surface hardness tests. Unfortunately, this instrument's maximum aperture is only 50mm, many large number of stamping dies can not be tested . Opening of 100mm and 200mm surface Rockwell hardness being developed, then a large part of stamping dies can be tested in the field .

Stamping mold surface heat hardened layer depth can Vickers or Knoop hardness testing. Detection method can refer to the author's other articles on the site .

After heat treatment of the test surface hardness of steel stamping dies , there is a wrong approach worth corrected. This is the inappropriate use of such occasions in the hardness . The advantage of Leeb hardness tester is lightweight, with a computer , using a simple , converted into a variety of hardness values ​​are very convenient. But the problem is that it can only test thick workpieces , workpiece material with a single test . For a surface-hardened layer of the workpiece can not test the exact hardness value, because this is not a single piece of material . This is the principle of Leeb hardness determined .Cloth, Luo, Victoria are three commonly used static hardness testing principle , all will be a hard head slowly pressed into the surface of the sample , and then test the indentation depth or size to determine the hardness value size. The Leeb hardness tester uses a dynamic test principle . It is a sphere of specified quality impact of the sample surface at a predetermined speed , test it with the initial velocity of the rebound velocity difference , in order to determine the hardness of the sample values. Leeb hardness testing of materials is by determining rebound hardness . It is applied to the kinetic energy of the sample along the direction of the force transmitted to the deep part ( at least to a depth of a few centimeters ) . To understand this , just look in the hardness of the standard hardness block how thick the clear. If there are two same size , the same hardness of the workpiece surface and the same for the nitriding process , the same nitrided layer hardness , but a thickness of 0.5mm, the other is 1.0mm. Then if Leeb hardness test hardness of the workpiece will obviously give different results . It is clearly out of the measured hardness value is neither the hardness of nitrided layer , nor is the hardness of the substrate , but the result of the two , because the surface layer thickness, is bound to lead to different results.Conclusion is Leeb hardness tester can not be used with a surface hardened layer of the workpiece.

3 , stamping parts stamping intermediate products and finished hardness testing
Stampings Stampings intermediate products and finished products can be used hardness test Rockwell hardness . Some stamping parts is relatively small , but with a more complicated shape , can be used to test a small plane , stamping parts such hardness can not be detected on a common desktop . The company's portable Rockwell / Superficial Rockwell hardness test small parts can be coupled with a dedicated point anvil , its supporting surface is small, many small stampings complex shape can be detected with this instrument . The instrument if accompanied by a support base made ​​of cast iron , you can also use your desktop fooled desktop , you can do the bulk of the small stamping parts piece by piece .

For all kinds of metal sheet stampings, you can use the company's portable surface Rockwell hardness testing. For thin stampings, you can use our portable surface Rockwell hardness tester with diamond anvil point test its hardness HR30Tm . For punching into thin tubular stampings, you can use the company's portable Rockwell hardness test tubes , stampings bore diameter can be as small as 4.8mm.

In short, the hardness test for metal stamping parts processing industry is very important , most cases can be used Rockwell hardness testing. The company's portable Rockwell / Superficial Rockwell hardness due portable, high accuracy , low price, the test is simple .In stamping parts processing industry has a broad application prospects. This instrument worthy of attention and adoption.