Correlation between Mechanical Properties and Microstructure as a Function of W content in Ni-W Dual-Phase Alloys
Correlation between Mechanical Properties and Microstructure as a Function of W content in Ni-W Dual-Phase Alloys
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Ni-W 双相合金中 W 含量与机械性能和微观结构之间的相关性
DOI：
10.1166/sam.2016.2825
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发表时间：
2016
影响因子：
0.9
通讯作者：
Tomotaka Miyazawa and Thoru Yamasaki
中科院分区：
文献类型：
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作者：
Shota Nakayama;Hiroki Adachi;Takayuki Nabeshima;Tomotaka Miyazawa and Thoru Yamasaki
在本研究中，研究了Ni-W合金的力学性能与显微组织随W含量变化的关系。特别是，我们重点研究了用刷涂技术制备的Ni-W合金的本征延展性。通过改变镀液温度，电沉积了不同W含量的Ni-W合金。高分辨电子显微镜和X射线衍射仪测试表明，W含量小于14at.%的Ni-W合金由纳米晶单相组成，而W含量在14.5~17.0at.%的Ni-W合金由纳米晶-非晶双相组成。在Ni-W双相合金中，无论W含量如何，平均晶粒度都在6 nm左右。因此，纳米晶相的体积分数随着W含量的增加而单调下降。纳米晶Ni-W合金的抗拉强度约为2400 Mpa，塑性较低。由纳米晶和非晶相组成的Ni-W双相合金具有约6.5%的大塑性应变，最大抗拉强度高达∼2500 Mpa。通过同步辐射X射线衍射仪测量，证实了Ni-W双相合金中存在形变诱导的晶界长大。这种颗粒长大会导致强度的增加。因此，Ni-W双相合金具有加工硬化能力，可以改善拉伸塑性。
In this study, the correlation between mechanical properties and microstructure was investigated in Ni–W alloys as a function of W content. In particular, we focus on the intrinsic ductility of Ni–W alloys fabricated by using a brushing technique. Ni–W alloys with varying W content were electrodeposited by the change in temperature of the plating bath. High-resolution transmission electron microscopy and XRD measurements revealed that Ni–W alloys with a W content of less than 14 at.% consisted of a nanocrystalline single phase, while those with W contents between 14.5 and 17.0 at.% consisted of a nanocrystalline-amorphous dual phase. In the Ni–W dual-phase alloys, the average grain size was about 6 nm, regardless of the W content. Thus, the volume fraction of the nanocrystalline phase decreased monotonically with increasing W content. The nanocrystalline Ni–W alloys exhibited a tensile strength of about 2400 MPa and low ductility. Ni–W dual-phase alloys consisting of a nanocrystalline and an amorphous phase exhibited a large plastic strain of about 6.5% with a maximum tensile strength as high as ∼2500 MPa. Through synchrotron radiation X-ray diffraction measurements, the emergence of deformation-induced grain growth was confirmed in the Ni–W dual-phase alloy. This grain growth leads to an increase in strength. Thus, Ni–W dual-phase alloys possess work-hardening ability and can improve the tensile ductility.