F Engineering stress: Engineering strain: 1-1 e True stress: True strain: PDF文件使用"pdfFactory Pro'”试用版本创建um,fineprint.com,cn Engineering stress: Engineering strain: True stress: True strain: A 0 F s = 0 0 l l - l e = A F s t = ò = = A A l l l dl 0 0 ln ln PDF 文件使用 "pdfFactory Pro" 试用版本创建 ÿwww.fineprint.com.cn