The use of non-magnetic alloys will become increasingly widespread

       The development and production of non-magnetic cemented carbide materials is a significant performance for new cemented carbide materials.



Carbide is based on the periodic table IVA, ⅤA, ⅥA refractory metal carbide (such as tungsten carbide WC), iron group transition metal (cobalt Co, nickel Ni, iron Fe) as a binder phase, through the powder Metallurgical industry sintered.





The above tungsten carbide is non-magnetic, and Fe, Co, Ni are magnetic, the Curie point were 770 ℃, 1120 ℃, 354 ℃. The Ni (nickel) Curie point is relatively low, can be some way to lower it below room temperature, with Ni as a binder is a prerequisite for the preparation of non-magnetic alloy.



WC-Ni alloy and WC-Co alloy, the carbon content is the main factor affecting the solid content of W in the binder phase, that is, the lower the carbon content of the carbon compound phase in the alloy, the lower the solid solution of W in the Ni bond phase Large, the range of about 10 to 31%.



When W in the Ni binder phase in the amount of solid solution more than 17%, the alloy was non-magnetic. The essence of this method is to reduce the carbon content, improve the W in the binder phase of the amount of solid solution to obtain non-magnetic cemented carbide.



The actual use of carbon content is less than the theoretical carbon content of WC powder, or in the mixture by adding W powder method to achieve the purpose of producing low-carbon alloy.However, the use of simple control of carbon content to produce non-magnetic alloy is very difficult.



For the method of adding Cr to produce a non-magnetic alloy, the magnetism does not depend on the change in the carbon content of the alloy. However, the strength of the alloy after the addition of Cr3C2 (chromium carbide) is affected.



The current production of non-magnetic cemented carbide, non-magnetic important indicator is the high permeability, its mechanical properties (strength, hardness, wear resistance, etc.) to be further improved.