Crystallographic Study of Diffusion Phase Transformations for Martensites with Complex Structure

复杂结构马氏体扩散相变的晶体学研究

• 批准号: 03452243
• 负责人: OTSUKA Kazuhiro
• 金额: $ 4.42万
• 依托单位: University of Tsukuba
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-03452243/
• 关键词: diffusionaless phase transformation; crystallography phase transformation; phenomenological theory; 7R martensite; Ni-Al; Au-Cd; self-accommodation; lattice invariant shear; マルテンサイト変態; NiーAl合金; AuーCol合金; 形状記憶合金; マルテンサイト変態の結晶石; 理象論; 構造解析

There is a beautiful phenomenological theory for the crystallography of diffusionaless phase transformations called martensitic transformations, which were developed by Wechsler-Lieberman-Read and Bowles-Mackenzie. However, there still remain alloys, for which the crystallography of the transformations are still not yet established. It is the purpose of the present work to study them in detail, and to obtain the unified view for the martensitic transformations. We picked up B2->14M(7R) transformation in Ni-Al alloys and beta_2 (B2)->zeta_2'(trigonal) transformations in a Au-49.5at%Cd alloy as such cases. First, we found that the phenomenological crystallographic theory applies well for the B2->14M transformation. The self-accommodation of the alloy was also studied, and we proposed a new basic morphology called "the parallelogran morphology" instead of the previously proposed "diamond morphology". Furthermore, in Ni-Al-Mn alloys, we found new martensite structures designated as 10M(15M) and 12M(36M), which have not been found in other alloys either. For the latter Au-49.5at%Cd alloy, we determined the structure of the zeta_2' martensite, which have been undetermined for 50years. On the beta_2->zeta_2' transformation, Ledbetter assumed the presence of a lattice invariant shear, while Tadaki et al.deined the presence. In the present study, we found two types of martensite morphologies called roof-type and herring-bone type, in which the former has a lattice invariant shear while the latter does not. Thus, we reconciled the big inconsistency between the two researchers. from the above results, we conclude that the phenomenological crystallographic theory applies well even for the martensites with complex structures, if the lattice invariant shear is chosen correctly.

对于无扩散相变的结晶学，有一种美丽的唯象理论，称为马氏相变，它是由Wechsler-Lieberman-Read和Bowles-Mackenzie发展起来的。然而，仍然存在合金，其相变的结晶学仍未建立。本工作的目的是对它们进行详细的研究，以获得对马氏体相变的统一看法。我们在Ni-Al合金中发现了B2-&Gt；14M(7R)相变，在Au-49.5at%Cd合金中发现了β_2(B2)-&Gt；Zeta_2‘(三角)相变。首先，我们发现唯象结晶学理论很好地适用于B2-&gt；14M相变。我们还研究了该合金的自适应行为，提出了一种新的基本形态，称为平行四边形形态，而不是以前提出的“钻石形态”。此外，在Ni-Al-Mn合金中，我们发现了新的马氏体组织，命名为10m(15m)和12m(36m)，这在其他合金中也没有发现。对于后者的Au-49.5at%Cd合金，我们测定了50年来一直没有确定的Zeta_2‘马氏体的结构。关于Beta_2-&gt；Zeta_2‘变换，LedBetter假设存在晶格不变剪切，而Tadaki等人则认为存在晶格不变剪切。在本研究中，我们发现了两种类型的马氏体形态，即屋顶型和鱼骨型，前者具有晶格不变剪切，而后者不具有晶格不变剪切。因此，我们调和了两位研究人员之间的巨大矛盾。从以上结果可以看出，只要选择正确的晶格不变剪切力，唯象结晶学理论即使对于结构复杂的马氏体也能很好地适用。

项目成果

Y.Murakami, K.OtsukaS.Hanada and S.Watanage: "Mechanism of Self-accommodation of 7R Martensite in a Ni-37.0at%Al Alloy" Proc.IUMRS Int.Conf.on Advanced Materials. 9 (in press). (1993)

Y.Murakami,%20K.OtsukaS.Hanada%20and%20S.Watanage:%20"机制%20of%20自调节%20of%207R%20马氏体%20in%20a%20Ni-37.0at%Al%20Alloy"%20Proc.

S.Morito, T.Inoue, K.Oda and K.Otsuka: "Electron Microscopy Observations of 15R and12-layrs Martensites in Ni_<50>Al_XMn_<50-X> Alloys" Proc.IUMRS Int.Conf.on Advanced Materials. 9 (in press). (1993)

S.Morito、T.Inoue、K.Oda 和 K.Otsuka：“Ni_<50>Al_XMn_<50-X> 合金中 15R 和 12 层马氏体的电子显微镜观察”Proc.IUMRS Int.Conf.on Advanced Materials。

T.Inoue,S.Morito,Y.Murakami,K.Oda: "New Martensite Structures and Composition Dependence of Martensitic Transformations in Ni_<50>Al_xMn_<50-x> Alloys" Materials Letters. (Submitted to). (1993)

T.Inoue、S.Morito、Y.Murakami、K.Oda：“Ni_<50>Al_xMn_<50-x> 合金中马氏体转变的新马氏体结构和成分依赖性”材料快报。

Y.Emura: "Crystal Structure of ζ^´_2 Martensite in Auー49.5at%Cd Alloy" Proceedings of MRS Meeting(Boston,1991). M. (1992)

Y.Emura：“Auー49.5at%Cd 合金中 z^´_2 马氏体的晶体结构”MRS 会议记录（波士顿，1991 年）。

Y.Murakami,K.Otsuka,S.Hanada and S.Watanabe: "Crystallography of Stress-Induced B2→7R Martensitic Transformation in a Ni-37.0at%Al Alloy" Materials Transactions,JIM. 33. 282-288 (1992)

Y. Murakami、K. Otsuka、S. Hanada 和 S. Watanabe：“Ni-37.0at%Al 合金中应力诱导的 B2→7R 马氏体转变的晶体学”Materials Transactions，JIM 33. 282-288 (1992)。