金属学报  1956, Vol. 1 Issue (4): 347-366

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滚珠钢在室温到马氏体点温度范围内等温转变的性质

张沛霖;徐萃章

中国科学院金属研究所;中国科学院金属研究所

NATURE OF ISOTHERMAL TRANSFORMATION BETWEEN ROOM TEMPERATURE AND MARTENSITE POINT IN A BALL-BEARING STEEL

CHANG PEI-LIN AND HSU TSUI-CHANG Institute of Metal Research;Academia Sinica

张沛霖;徐萃章. 滚珠钢在室温到马氏体点温度范围内等温转变的性质[J]. 金属学报, 1956, 1(4): 347-366.
, . NATURE OF ISOTHERMAL TRANSFORMATION BETWEEN ROOM TEMPERATURE AND MARTENSITE POINT IN A BALL-BEARING STEEL[J]. Acta Metall Sin, 1956, 1(4): 347-366.

摘要 参考文献 相关文章 Metrics 全文: PDF(1909 KB)   摘要: 用电阻法研究了含1.43%Cr,1.02%C的滚珠钢在室温到马氏体点(159℃)温度范围内奥氏体等温转变过程。结果指出在这一温度范围内的等温转变是以马氏体转变的形式进行的,而不产生中温转变形式的等温转变。当样品由1100℃淬火至室温后再“上淬”至低于马氏体点的温度进行等温保持时,部分的残留奥氏体即等温转变为马氏体。根据动力学的考虑,这一转变很可能不是通过形成新的晶核,而是已有马氏体晶体的长大过程。同时,这种转变主要受已有马氏体回火过程的控制。在100℃左右长期等温保持时可以得到最大的残留奥氏体转变量。更高或更低的温度,在同一时间内转变量都较100℃左右为小,这可作为精密量具刃具实际热处理的参考。 Abstract：The isothermal transformation of austenite in a ball-bearing steel within thetemperature range between martensite point M and room temperature has been investigated by electrical resistance measurements.The steel employed was ofcommercial production containing 1.43% Cr and 1.02% C and its martensite pointis 159℃ when quenched from 1100℃.The specimen was first quenched toroom temperature(in which state it contained 17% retained austenite),and thenupquenched to isothermal bath in which its transformation was followed.Theeffect of tempering of martensite was eliminated by employing two specimens ofdifferent martensite contents.1)By comparing the kinetics of isothermal transformation below and abovemartensite point,it was concluded that isothermal transformation below M pointtakes place by the martensite process and not by intermediate transformation(bainitic),in.spite of the presence of large amount of martensite and relativelyhigh temperature at which the transformation takes place.2)From kinetics considerations it appears that isothermal transformationof retained austenite to martensite takes place not by the formation of new nuc-lei but mainly by the growth of already existing martensite.This would alsoinfer that coherency between martensite and austenite is not destroyed(or notcompletely destroyed)during quenching transformation.3)The tempering of martensite appears to be the controlling process forthe isothermal transformation of retained austenite to martensite,such that theelastic strain energy relaxed by tempering of martensite exceeds the difference offree energies between the two phases.The activation energy of tempering ofmartensite within the temperature range considered(below 150℃)was found tobe 13,300 cal/mol,which compares favourably well with the value of 16,000 cal/molas given by Averbach and Cohen in 1953.4)The results show that isothermal keeping for prolonged duration at theneighbourhood of 100℃ brings about maximum amount of transformation of re-tained austenite.That is,at either higher or lower temperatures and for a speci-fied time,the amount of austenite-martensite transformation is less.This is signifi-cant for practical heat-treating of precision gauges and tools for which dimen-sional stability is important and high temperature tempering may not be de-sirable for hardness consideration. 收稿日期: 1956-04-18      服务 把本文推荐给朋友 加入引用管理器 E-mail Alert RSS 作者相关文章 张沛霖 徐萃章 44.8K 链接本文: https://www.ams.org.cn/CN/      或      https://www.ams.org.cn/CN/Y1956/V1/I4/347 [1] #12 [2] #12 [3] #12 [4] Kulin,S.A.and Speich,G.R.,Trans.AIME.194(1952) ,258． [5] Cech,R.E.and Hollomon,J.H.,Trans.AIME.197(1953) ,685． [6] Shih,C.H.(师昌绪),Averbach,B.L.and Cohen,M.,Trans.AIME,203(1955) ,183． [7] Machlin,E.S.and Cohen,M.,Trans.AIME,194(1952) ,489． [8] Fisher,J.C.,Acta Metallurgica,1,No.1(1953) ,32． [9] Howard,R.T.and Cohen,M.,Trans.AIME,176(1948) ,384． [10] #12 [11] #12 [12] #12 [13] #12 [14] Austin,C.R.,Trans.ASM,22(1934) ,31． [15] Slowter,E.E.and Gonser,B.W.,Metals and Alloys,8(1937) ,159-168,195-205． [16] Averbach,B.L.and Cohen,M.,Trans.ASM,41(1949) ,1024． [17] #12 [18] Roberts,C.S.,Averbach,B.L.and Cohen,M.,Trans.ASM,45(1953) ,576． [19] #12 [20] Ko,T.(柯俊),Acta Metallurgica,2,No.1(1954) ,75． No related articles found! Viewed Full text Abstract Cited   Shared      Discussed