Influence of Transformation Pseudoelasticity and Accumulated Plastic Strain on Low Cycle Fatigue Characteristics of Fe-30Mn-4Si-2Al Alloy
Influence of Transformation Pseudoelasticity and Accumulated Plastic Strain on Low Cycle Fatigue Characteristics of Fe-30Mn-4Si-2Al Alloy
复制标题
相变拟弹性和累积塑性应变对Fe-30Mn-4Si-2Al合金低周疲劳特性的影响
DOI：
10.2355/tetsutohagane.tetsu-2017-086
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
T. Sawaguchi
中科院分区：
文献类型：
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作者：
N. Nagashima;T. Sawaguchi
Fe-30 Mn-4Si-2Al合金（质量分数%）具有优异的低周疲劳性能。研究了Fe-30 Mn-4Si-2Al合金的疲劳特性与累积塑性应变的关系，并与Fe-28 Mn-6Si-Cr-0. 5 Nb-C合金和SUS 304钢的低周疲劳试验结果进行了对比。所得结果如下所示。Fe-30 Mn-4Si-2Al合金的疲劳寿命在所有应变范围内均最长，而Fe-28 Mn-6Si-5Cr-0.5NbC合金和SUS 304钢的疲劳寿命最短。特别是在高应变幅试验中具有较长的使用寿命。Fe-30 Mn-4Si-2Al合金的ε pa -Nf特性呈直线关系（ε pa = Cp/NfKp）。得到了Manson-Coffin规则成立的结果。此外，C p = 5.62，K p = 0.72，这是一个极高的值。由Manson-Coffin方程得到的Fe-30 Mn-4Si-2A合金的疲劳损伤值D接近1，与Fe-28 Mn-6Si-5Cr-0.5NbC合金或SUS 304钢相似。但累积塑性应变λ p与疲劳寿命N之间的关系远高于以前报道的Fe-28 Mn-6Si-5Cr-0.5NbC合金的极限λ p。特别是，ε ta = 2.0%和1.4%的结果是极限λ p的20倍。结果表明，Fe-30 Mn-4Si-2Al合金具有优异的低周疲劳寿命是由于其塑性应变积累缓慢和极高的Cp、Kp值所致。结果表明，ε马氏体正、逆相变时，部分位错的重复运动缓慢进行，重复变形组织和疲劳裂纹的发展过程沿沿着γ/ε界面呈"之“字形扩展。其结果是，它同意以前报道的事实，裂纹扩展受到抑制。
Synopsis Fe-30Mn-4Si-2Al alloy (mass%) was reported to show excellent low cycle fatigue properties. We investigated fatigue characteristics of the Fe-30Mn-4Si-2Al alloy as a function of accumulative plastic strains, comparing with the low cycle fatigue test results of Fe-28Mn-6Si-Cr-0.5Nb C alloy and SUS304 steel. The obtained results are shown below. The fatigue life of Fe-30Mn-4Si-2Al alloy is the longest in all the strain ranges as compared with Fe-28Mn-6Si-5Cr-0.5NbC alloy and the SUS 304 steel. In particular, it has a long life in test of high strain amplitude. The ε pa - N f characteristics of Fe-30Mn-4Si-2Al alloy show a straight relationship ( ε pa = C p / N f Kp ). The result that the Manson-Coffin rule holds was obtained. In addition, C p = 5.62, K p = 0.72, which is an extremely high value. The fatigue damage value D obtained from the Manson-Coffin equation of Fe-30Mn-4Si-2A alloy was almost 1, similar to Fe-28Mn-6Si-5Cr-0.5NbC alloy or SUS 304 steel. However, the relationship between the accumulative plastic strain λ p and fatigue life N is much higher than the limit λ p of Fe-28Mn-6Si-5Cr-0.5NbC alloy obtained in the previous report. In particular, the results of ε ta = 2.0% and 1.4% were 20 times the limit λ p . It was found that the excellent low cycle fatigue life of Fe-30Mn-4Si-2Al alloy is caused by the much slower accumulation of plastic strain and the extremely high values of C p and K p . The above results show that the repetitive motion of partial dislocation progresses slowly as ε martensite repeats normal and reverse transformation and the developmental process of repeated deformed tissue and fatigue crack propagates in a zigzag along γ/ε interface. As a result, it agrees with previously reported fact that crack growth is suppressed.