CAJ | 학술논문

通过Gleeble3800热/力模拟实验机研究了不同冷却速度对GCr15轴承钢组织转变的影响，通过对动态CCT曲线及不同冷速下的金相组织和显微硬度分析，结果表明：随着冷却速度的增加，晶界处二次碳化物由网状分布逐渐变为半网状、短条状分布，珠光体球团直径明显细化，CCT曲线得到的珠光体析出温度区间主要集中在600-700℃范围，继续升高冷却速度测定的将会出现马氏体，马氏体的转变温度为187℃，终轧后通过控制冷却速度可以达到控制组织转变类型的目的。
통과Gleeble3800열/력모의실험궤연구료불동냉각속도대GCr15축승강조직전변적영향，통과대동태CCT곡선급불동랭속하적금상조직화현미경도분석，결과표명：수착냉각속도적증가，정계처이차탄화물유망상분포축점변위반망상、단조상분포，주광체구단직경명현세화，CCT곡선득도적주광체석출온도구간주요집중재600-700℃범위，계속승고냉각속도측정적장회출현마씨체，마씨체적전변온도위187℃，종알후통과공제냉각속도가이체도공제조직전변류형적목적。
Different cooling processes simulation was conducted by Gleeble3800 thermal / mechanical simulator. The dynamic CCT diagram was established, microstructure andhardness of experimental specimens were analyzed. The research show that the secondary carbide in the grain boundary convers from network to half network, strip distribution and the diameter of pearlite nodule obviously refined with the increase of cooling rates for GCr15 bearing steel. The precipitation temperature of pearlite obtained from CCT curves mainly concentrated in the range of 600-700℃, with the cooling rate increasingpartial austenite transformed to martensite astemperature lower than 187℃, by control the cooling rate change the type of microstructure transformation.