钛合金相变点与微观组织研究  

Transformation Temperature of Titanium Measured by DSC

作　　者：张红菊 郭荣贵 张东晖 夏雯 刘淑凤 钟赢葆 王书明 Zhang Hongju;Guo Ronggui;Zhang Donghui;Xia Wen;Liu Shufeng;Zhong Yingbao;Wang Shuming(Guobiao(Beijing)Testing&Certification Co.,Ltd.,Bejing 100088,China)

机构地区：[1]国标(北京)检验认证有限公司,北京100088

出　　处：《稀有金属》2024年第10期1388-1395,共8页Chinese Journal of Rare Metals

基　　金：工业和信息化部2019年国家新材料测试评价平台建设项目——有色金属材料行业(TC190H3ZW/2)资助。

摘　　要：采用示差扫描量热法对α型、α+β型和亚稳定β型钛合金分别测定了β相变点温度,采用金相显微镜(OM)对相变点测量过程中样品的微观组织进行了观察分析,研究了不同升温速率对差示扫描量热法(DSC)结果的影响,并与金相法测量结果进行了比对。结果表明:示差扫描量热法可适用于α型、α+β型和亚稳定β型3种类型的钛合金相变点测量,对于热加工态或固溶态亚稳定型β钛合金建议在DSC测量之前进行热处理,确保足够α相析出;对于锻造α+β两相钛合金,由于DSC升温、降温过程中钛合金组织形态的差异和转变,导致首次测量与之后测量结果偏差较大,结果应以首次之后测量数据为准;示差扫描量热法与金相法测定β相变点数据接近,由于钛合金低导热系数的特点和升温速率过快导致测量热滞后效应,升温速率过慢又导致DSC灵敏度降低、热效应不明显,建议DSC测量升温速率采用20℃·min^(-1)。βtransus temperature(Tβ)is a very important process parameter.Due to the fluctuation of composition and different content of interstitial elements,the phase transformation temperature of titanium alloy products of the same brand and different batches can have a deviation of tens of degrees.In order to ensure the quality stability of materials,βphase transformation temperature of each batch of titanium materials is measured in industrial production.At present,Thermal analysis method and metallographic method are commonly used for measuring the transformation point of titanium alloy.In this paper,it was measured by differential scanning calorimetry forβtransformation temperature ofα-type,α+β-type and metastableβ-type titanium alloys to analyze the applicability of transition temperature in differential scanning calorimetry(DSC).The microstructure of the sample was observed and analyzed by metallographic microscope during DSC measurement process,the influence mechanism of phase transformation,room temperature and high temperature microstructure of titanium alloy on DSC measurement data was studied.The effect of heating rate on DSC results of TC4 sample was studied to observe the optimal DSC parameter.At the same time,in order to determine the accuracy of DSC method in measuring the transformation point temperature of titanium and titanium alloy,the metallographic method was used for data comparison and analysis.The results showed that DSCcould be used to measureβphase transformation point of various types of titanium alloys.According to metastableβ-type titanium,especially in hot working state or solid solution state,there was no obvious endothermic/exothermic peak in DSC curve,it was suggested thatβtitanium alloys could be heat treated in 650℃/1 h+550℃/1 h air cooling(AC)before DSC measurement to ensure sufficientαphase precipitation.For forgingα+β-type titanium alloy,due to the difference and transformation of titanium alloy microstructure during DSC heating and cooling,there was a large deviatio

关 键 词：相变点 显微组织 金相组织 示差扫描量热(DSC) 

分 类 号：TG146[一般工业技术—材料科学与工程]