Fatigue crack nucleation behavior in nickel-based PM alloy
The present paper describes the study on the fatigue behavior of an advanced nickel-based powder metallurgy alloy FGH95.It was observed that when the specimen subjected to very high stress (near yield strength),fatigue microcracks nucleated from slip bands at quite earlier fatigue stage,but they might not grow for most of the fatigue life.In order to understand the mechanism,a sectioning technique by means of focus ion beam was applied.The slip bands and the microcracks were cut to the depth of some micrometers.It was found that the slip bands and microcracks penetrated to the bulk material very shallow.From the view of the cutting profile of a real microcrack,the penetration to the bulk material was evident.It is concluded that the crack nucleation life should be determined when the crack open is observed.
Fatigue crack nucleation Crack initiation Powder metallurgical superalloy Focus ion beam Slip bands
Xinyue Huang Huichen Yu Rui Ma
Beijing Institute of Aeronautical Materials,Beijing 100095,China
国际会议
成都
英文
291-295
2009-10-16（万方平台首次上网日期，不代表论文的发表时间）