Abstract Based on the continuum damage mechanics, a new damage model has been developed for fatigue-creep interaction in this paper. This model researched the damage of fatigue, creep and their interaction respectively. In order to apply this model to the practical engineering condition, fatigue-creep interaction experiments have been carried out to research the damage evolution. These tests are conducted at 540℃ under stress control, using a trapezium waveform with the hold-time per cycle. Cylindrical specimens of 1.25Cr0.5Mo steel were used in the fatigue-creep interaction experiments. According to the experiments, the changing rule of mean strain has been studied in this paper. Defining the change of mean strain as the damage variable, damage curves of different stress ranges have been obtained based on the damage model the above damage model. Results showed that the values of damage calculated from the damage variable definition mentioned above were in good agreement with these damage curves. Besides, based on the damage model and the change rules of mean strain, this paper also discusses the failure assessment in engineering. A method to prevent the rupture of engineering components has been proposed in this paper.
[1]Plumbridge W J,Dean M,Sand Miller D A.Fatigue Eng Mater Struct,1982;5(1):101 [2]Kachanov L M.Isv Akad Nauk SSA Otd Tekh,1958;8: 26 [3]Robotnov Y N.Creep Problems in Structure Members. Amsterdam:North-Holland,1969 [4]Lemaitre J,Chaboche J L.Mechanics of Solid Materials. Cambridge:Cambridge University Press,1990 [5]Krajcinovic D,Lemaitre J.Continuum Damage Mechan- ics:Theory and Application.Berlin:Springer Verlag, 1987:37 [6]Bhattacharya B,Ellingwood B.Int J Solids Struct,1999; 36:1757 [7]Yaguchi M,Nakamura T,Ishikawa A,Asada Y.Nucl Eng Des,1996;162(1):97 [8]Dai Z Y,Zhai J,Li Q.J Southwest Jiaotong Univ,1998; 33(1):30 (戴振雨,翟己,黎强．西南交通大学学报,1998;33(1): 30) [9]Xiong X R.Jiangxi Sci,2005;23(1):9 (熊先仁．江西科学,2005;23(1):9) [10]Jing J P,Meng G.Proc CSEE,2003;23(9):167 (荆建平,孟光．中国电机工程学报,2003;23(9):167) [11]Lou Z W.Principle of Damage Mechanics.Xi'an:Xi'an Jiaotong University Press,1991:104 (楼志文．损伤力学基础．西安:西安交通大学出版社,1991: 104) [12]Lemaitre J.Nucl Eng Des,1984;80:233 [13]Lemaitre J.J Eng Mater Technol——Trans ASME,1979; 101:284 [14]Lemaitre J,Chaboche J L.Mechanics of Solid Material. Cambridge:Cambridge University Press,1990 [15]Chen L,Jiang J L.Acta Metall Sin,2005;41:157 (陈凌,蒋家羚．金属学报,2005;41:157) [16]Lemaitre J.J Eng Mater Technol——Trans ASME,1985; 107:83 [17]Tai W H.Eng Fract Mech,1990;37:853 [18]Wang T J.Eng Fract Mech,1992;42:177 [19]Chandrakanth S,Pandey P C.Eng Fract Mech,1995;50: 457 [20]Yang X H,Li N,Jin Z H,Wang T J.Int J Fatigue,1997; 19:687 [21]Wu H Y.Damage Mechanics.Beijing:National Defence Industry Press,1990:29 (吴鸿遥．损伤力学．北京:国防工业出版社,1990:29) [22]Yang G S.Damage Mechanics and Composite Material Damage.Beijing:National Defence Industry Press,1995: 18 (杨光松．损伤力学与复合材料损伤．北京:国防工业出版社, 1995:18) [23]Fan Z C,Jiang J L,Chen X D.J Zhejiang Univ(Eng Sci),2006;40:317 (范志超,蒋家羚,陈学东．浙江大学学报(工学版),2006;40: 317) [24]Yang T C,Chen L,Fan Z C,Chen X D,Jiang J L.Pres- sure Vessel Technol,2005;154(9):6 (杨铁成,陈凌,范志超,陈学东,蒋家羚．压力容器,2005; 154(9):6)
