CAJ | 학술논문

提出了在非对称循环加载下描述材料弹塑性材料行为的损伤演变速率方程式与各个历程与不同损伤量Doi相对应的寿命Noi估算式.其方法是采用以塑性应变幅同弹性应变幅之比值Δεp/Δεe作为应力应变参量,以常用的材料常数作为材料参数.而且,还提出了与常用材料常数、平均应力与平均应变、加载临界历程长短有着函数关系的综合性材料常数的新概念.此外,以汽车的某一零件为例,计算了它的疲劳损伤.其计算结果与 Landgraf方程式计算结果一致,且计算精度较高.这对避免过多而重复的疲劳试验,对方便工程应用,对节约人力、时间和资金有着实际意义.
제출료재비대칭순배가재하묘술재료탄소성재료행위적손상연변속솔방정식여각개역정여불동손상량Doi상대응적수명Noi고산식.기방법시채용이소성응변폭동탄성응변폭지비치Δεp/Δεe작위응력응변삼량,이상용적재료상수작위재료삼수.이차,환제출료여상용재료상수、평균응력여평균응변、가재림계역정장단유착함수관계적종합성재료상수적신개념.차외,이기차적모일령건위례,계산료타적피로손상.기계산결과여 Landgraf방정식계산결과일치,차계산정도교고.저대피면과다이중복적피로시험,대방편공정응용,대절약인력、시간화자금유착실제의의.
Several new calculating equations on the damage-evolving rate are suggested for describing the elastic-plastic behavior of some materials under un-symmetric cyclic loading. And the estimating formulas are given of the life relative to varied damage value Doi at each loading history. The method is to adopt the ratio of plastic strain range to elastic strain range as the stress-strain parameter, using the staple material constants as the material parameters in damage calculating expression. And it gives out a new concept of the compositive material constant, that has a functional relation with the staple material constants, average stress,average strain and critical loading time. In addition, it calculates fatigue damage as example for a part of car, its calculating results are accordant with the Landgraf's equation, and calculating precision is more rigorous, so could avoid unnecessary fatigue tests and will be of practical significance to stint times, manpower and capitals, and to provide convenience for engineering applications.