Method for preparing superfine hard alloy

Abstract

The invention relates to a preparation method of ultrafine cemented carbide for manufacturing micro-drills, comprising: batching, wet grinding, drying, pressing and sintering processes, and the selected HCP value is (38-41)KA / m when batching WC powder and Co powder with a weight percentage of 7.8% to 8.2%, and VC with a weight percentage of 0.28% to 0.30%, 0.31% to 0.35% TaC, and 0.31% to 0.35% Cr 3 C 2 , VC, TaC and Cr 3 C 2 The total weight percentage is 0.95%~1.0%. When calculating the ingredients, the carbon balance value is (+0.26~+0.28)%, and the average grain size of WC in the cemented carbide reaches (0.3~0.4)μm. Using the above preparation method, the hardness of the prepared cemented carbide can reach HV 3 : 1900 ~ 1980, and the minimum diameter of the PCB micro-drill made of this kind of ultra-fine cemented carbide can be as small as 0.3mm.

Description

Technical field:

[0001] The invention relates to a preparation method of ultrafine hard alloy, in particular to a preparation method of WC-Co ultrafine hard alloy used for manufacturing micro drills. Background technique:

[0002] Cemented carbide can be used to manufacture PCB micro-drills due to its high hardness and high strength. With the rapid development of the electronics industry, PCB micro-drills with smaller drill diameters are required. At present, domestic cemented carbide materials can generally only manufacture PCB micro-drills with a diameter of 0.8 mm or more, which is difficult to meet the requirements of the development of the electronics industry. Invention content:

[0003] The purpose of the present invention is to provide a kind of preparation method of superfine cemented carbide, the cemented carbide that makes with this method can be used for making the microdrill below 0.8mm of drill diameter.

[0004] In order to achieve the above object, the pr...