Very High Cycle Fatigue Behavior of a Directionally Solidified Ni-Base Superalloy DZ4.
Very High Cycle Fatigue Behavior of a Directionally Solidified Ni-Base Superalloy DZ4.
复制标题
定向凝固镍基高温合金 DZ4 的极高循环疲劳行为
DOI：
10.3390/ma11010098
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发表时间：
2018-01-10
期刊：
影响因子：
--
通讯作者：
Sun H
中科院分区：
文献类型：
--
作者：
Nie B;Zhao Z;Liu S;Chen D;Ouyang Y;Hu Z;Fan T;Sun H
研究了铸造气孔对定向凝固镍基高温合金DZ 4超高周疲劳性能的影响。铸造和热等静压（HIP）试样进行了非常高的循环疲劳载荷在环境大气中。结果表明，铸态和热等静压态试样的S-N曲线均呈现连续下降的趋势。由于消除了铸造气孔，HIP样品比铸造样品具有更好的疲劳性能。在低应力幅下，亚表面裂纹起源于铸造试样中的铸造孔隙，而热等静压试样的疲劳裂纹则起源于晶体学刻面脱粘。当考虑铸造气孔作为初始裂纹时，存在一个临界应力强度阈值，其范围为1.1 ~ 1.3MPam，低于该阈值，疲劳裂纹不会从铸造气孔中萌生。此外，基于修正的El Haddad模型估算了铸件气孔对疲劳极限的影响，与实验结果吻合较好。使用疲劳指示参数（FIP）模型可以很好地预测铸造和HIP试样的疲劳寿命。
The effect of casting pores on the very high cycle fatigue (VHCF) behavior of a directionally solidified (DS) Ni-base superalloy DZ4 is investigated. Casting and hot isostatic pressing (HIP) specimens were subjected to very high cycle fatigue loading in an ambient atmosphere. The results demonstrated that the continuously descending S-N curves were exhibited for both the casting and HIP specimens. Due to the elimination of the casting pores, the HIP samples had better fatigue properties than the casting samples. The subsurface crack initiated from the casting pore in the casting specimens at low stress amplitudes, whereas fatigue crack initiated from crystallographic facet decohesion for the HIP specimens. When considering the casting pores as initial cracks, there exists a critical stress intensity threshold ranged from 1.1 to 1.3 MPam, below which fatigue cracks may not initiate from the casting pores. Furthermore, the effect of the casting pores on the fatigue limit is estimated based on a modified El Haddad model, which is in good agreement with the experimental results. Fatigue life for both the casting and HIP specimens is well predicted using the Fatigue Indicator Parameter (FIP) model.
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影响因子：
6
作者：
Mayer, H;Papakyriacou, M;Stanzl-Tschegg, SE
通讯作者：
Stanzl-Tschegg, SE
DOI：
10.1115/1.3443647
发表时间：
1979-01-01
影响因子：
1.2
作者：
ELHADDAD, MH;SMITH, KN;TOPPER, TH
通讯作者：
TOPPER, TH
影响因子：
6
作者：
Bathias, Claude
通讯作者：
Bathias, Claude
影响因子：
4
作者：
Carter, TJ
通讯作者：
Carter, TJ
影响因子：
5.4
作者：
Beretta, S.;Carboni, M.;Madia, M.
通讯作者：
Madia, M.