What is the heat treatment process of cemented carbide?
To put it plainly, that is, hardening of cemented carbide, that is, heating to a certain temperature, insulation for a certain period of time, and then suddenly into the inert gas, so that it suddenly cooling.. The same as steel quenching. After quenching generally tempered, to eliminate the stress produced by quenching, it is mainly to change the bonding phase components, that is, the organizational structure, improve the strength of cemented carbide, hardness and comprehensive performance
Responsible for this, you said, carbide heat treatment is deceptive theory, try to eliminate the gap, improve the purity of the fly.
The common heat treatment process of steel bonded carbide is spheroidizing annealing, quenching and tempering.1, spheroidizing annealing die steel bonded carbide matrix is steel, as the alloy tool steel, need to be spheroidizing annealing treatment, can machine processing. The process of spheroidizing degradation is: heating 850~890 DEG C, holding 4h, and cooling the furnace to about 730 DEG C, holding 6h, the furnace is cold, and the air cooled below 500 degrees centigrade,2, the purpose is to make the quenching matrix transforms into martensite, obtain high mechanical properties, due to poor thermal conductivity, preheating, hard steel bonded carbide in carbide phase of austenite grain growth to deter, and the dissolution of carbide in the matrix alloy, iron and hinder the diffusion of carbon atoms, of austenite the grain growth plays an inhibitory effect, so the steel bonded hard alloy quenching overheating less than alloy tool steel, quenching temperature can be higher, the time may be longer, usually for WC type steel bonded hard alloy, quenching temperature of 1020~1050; for TiC type steel bonded hard alloy, quenching temperature is 950~1000 DEG C; G type steel bonded cemented carbide phase with high speed steel, quenching temperature of 1200~1280.3, steel bonded hard alloy die after quenching tempering should be timely, especially the large die should be timely, in order to eliminate quenching stress, prevent mold cracking, while tempering can adjust the organization to obtain the mechanical properties required, tempering temperature often take 180~200 C, 2h insulation, high toughness, high temperature tempering can be used as 500~650 C, but the need to avoid the brittle temperature zone at 250~350 DEG C, high temperature tempering, the carbide precipitation and residual austenite transformation, there will be two hardening, but high temperature tempering will cause precipitation of lead carbide link impact toughness decreases.
