How the heat treatment to affect Cr2MnSiV wear resistance
The study of wear resistant materials has been always the industry focus. The main wear-resistant materials are wear-resistant cast iron, high manganese steel, low and medium alloy wear-resistant cast steel.
Low and medium alloy wear-resistant cast steel has properties of high strength, good wear-resistance, and good impact resistance, which get more attention of people, and are applied to the lining board and hammer head.
Moreover, the alloy wear-resistant cast steel can adjust the comprehensive mechanical properties of the material in a wide range by adjusting the composition and heat treatment process.
Medium carbon Cr2MnSiVRE is wear-resistant cast steel, carry out oil quenching after heating at 900, 950, 1000 and 1050℃. The quenched samples were tempered at 250℃. With the increase of quenching temperature, the microstructure of the alloy is not obviously coarsening, but its uniformity is improved. This shows that with the increase of quenching temperature, Extension capability of carbon and alloy elements is enhanced, so that teh uniformity of each element in steel in austenite can be effectively improved, and the degree of solute segregation formation during solidification process of casting is improved.
The addition of trace V plays a role in refining grain. The quenching temperature increased from 900 to 1050℃, and the hardness values ranged from 54 to 53HRC, keeping high hardness, basically no change. However, the quenching temperature has a significant influence on the impact toughness. The impact toughness increases with the quenching temperature, and the impact toughness reaches 60J/cm2 at 1050℃ of quenching temperature.
Then the sample is quenched at 1050℃, and tempered at different temperatures (200, 250, 280 and 310℃) in the low temperature tempering zone. It is found that the impact toughness reached a maximum value of 60J/cm2 at temperiing temperature of 250℃. The impact toughness will decrease as below or above 250℃. The impact toughness tempered at 280℃ is slightly lower than that at 250℃, reaching 53J/cm2, but the impact toughness decreases remarkably after tempering at 310℃, only 21J/cm2.
The steel can obtain higher strength and good toughness after proper heat treatment.