Nucleation of isothermal martensite

✍ Scribed by A Borgenstam; M Hillert

• Book ID: 104402287
• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 233 KB
• Volume: 48
• Category: Article
• ISSN: 1359-6454
• DOI: 10.1016/s1359-6454(00)00101-4

✦ Synopsis

AbstractÐTwo methods of evaluating an activation energy for the nucleation of martensite from kinetic information on isothermal martensite are discussed. In both methods the nucleation is described as thermally activated growth of an embryo up to a size where rapid growth can get started. The ®rst method is based on the absolute value of the rate of reaction at each separate temperature and depends on the neglect of the reverse reaction. The second method is based on the temperature dependence of the rate at low temperatures and includes the reverse reaction and it typically yields a lower activation energy. It can be used to de®ne the region of low net driving force where the reverse reaction, which is neglected in the ®rst method, is important and that method should not be used. A uni®ed description of the nucleation of athermal and isothermal martensite is also presented.