title: A modified evaluation method to reduce finite pulse time effects in flash diffusivity measurement.
abstract: A modified evaluation method for laser flash is proposed. In this method, the moment of laser-heating cutoff time is considered as zero point. The penetration depth and formula equation of the sample temperature distribution are obtained with the approximate analytical solution before time zero (during laser heating) for the physical model of a continuously heated half-infinite, well-distributed sample. The weighted-average and approximate-equation methods are then used to quantitatively determine the laser effect depth, which leads to the formulation of a modified evaluation method in flash thermal diffusivity measurement. Results of the simulation calculations and experiments confirm the correctness of the modified method, which remarkably increases flash method applications. The modified method is applicable only to cases in which δ(x) does not exceed the sample thickness (√(12ατ0)≤L) during laser heating.
authors.affiliation: The Shanghai Institute of Ceramics, Chinese Academy of Sciences, No.1295 Dingxi, Load, 200050 Shanghai, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Tao
authors.affiliation: The Shanghai Institute of Ceramics, Chinese Academy of Sciences, No.1295 Dingxi, Load, 200050 Shanghai, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Yang
authors.affiliation: The Shanghai Institute of Ceramics, Chinese Academy of Sciences, No.1295 Dingxi, Load, 200050 Shanghai, China.
authors.forename: Qiu
authors.initials: Q
authors.lastname: Zhong
authors.affiliation: The Shanghai Institute of Ceramics, Chinese Academy of Sciences, No.1295 Dingxi, Load, 200050 Shanghai, China.
authors.forename: Zijun
authors.initials: Z
authors.lastname: Xu
authors.affiliation: The Shanghai Institute of Ceramics, Chinese Academy of Sciences, No.1295 Dingxi, Load, 200050 Shanghai, China.
authors.forename: Caiyun
authors.initials: C
authors.lastname: Luo