Process Of Heat Treatment Of Large Ball Mill Liner Wear Resistant Low-alloy Steel

ZG29Cr2Si2MnMoRE steel is a new adaptation to the large ball mill liners used as an excellent material.This paper first determined the critical transition temperature of the test of wear-resistant steel, determination of CCT curve and Austenitic expansion curve and to develop a heat treatment process based on CCT curve study the influence of annealing, quenching and tempering process on the microstructure and properties of the steel. By measuring the hardness toughness, tensile strength, abrasion resistance and fracture and wear morphology of the test steel under different heat treatments, and ultimately determine the optimum heat treatment process of the steel.Final analysis of experimental results obtained determined by the vertex ZG29Cr2Si2 MnMoRE steel on expansion curves austenite phase transition point is 1040 CCT curve can be obtained from the steel Ac1 = 910, Accm = 1040, Ms = 375, in order to determine the quenching temperature steel is 1040.Test steel occurred in 1040 ×2h after austenitization of its under three different conditions are water quenching, oil quenching, air-cooled quenching after quenching and tempering of the samples of three different temperatures tempering heat treatment time 4h.Finally, according to the test results obtained the sample hardness, tensile strength and impact toughness shows tempering temperature is 180, the performance of steel is best. And the performance of the sample from water quenching and oil quenching the results are similar, but considering the cost of the product, choose water quenching is superior. Impact toughness up to 49.57 J /cm2, hardness HRC reached 50.51, a tensile strength of 1250.69 MPa, the mechanical properties are good. Under the conditions of abrasive wear the wear properties of the 2# sample is best and the wear resistance than the rest of the sample by an average of 40%.Through the test material fracture morphology, the steel is mainly ductile fracture, fracture dimples evenly distributed and small, good toughness.