Ti 基および Cu 基ナノ結晶分散型バルク金属ガラスの疲労強度
Ti 基および Cu 基ナノ結晶分散型バルク金属ガラスの疲労強度
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DOI：
10.2320/jinstmet.70.816
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发表时间：
2006
影响因子：
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通讯作者：
和孝 藤田;哲郎 橋本;信行 西山;朝利 馬;久道 木村;明久 井上
中科院分区：
文献类型：
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作者：
和孝 藤田;哲郎 橋本;信行 西山;朝利 馬;久道 木村;明久 井上
对纳米晶钛基和铜基大块金属玻璃（BMG）进行了疲劳测试，但目前还没有关于疲劳强度的报道。采用铜模铸造法在纳米晶 Ti41.5Zr2.5Hf5Cu42.5Ni7.5Si1 at% 和 Cu60Zr30Ti10 at% 体系中制备直径为 2 mm 的试验合金棒。两种 BMG 中的纳米晶体均分散在金属玻璃相中。纳米晶Ti基和Cu基BMG的拉伸强度（σB）分别为2.04 GPa和2.00 GPa，杨氏模量分别为95 GPa和114 GPa。将测试样品加工成沙漏形状（轴向半径：4.45mm，最小直径：0.9mm），加工后样品表面电解抛光50~100μm。样本在 0.1 的应力比和 5-8 Hz 的频率下进行测试。纳米晶钛基和铜基 BMG 的疲劳极限 (σw)（总应力幅的一半）和疲劳比 (σw/σB) 显示出非常大的值（钛基合金；806 MPa 和 0.40，铜基合金；490 MPa 和 0.25）。该实验结果表明，纳米晶分散的BMG可能比具有高疲劳强度的高强度晶体合金（例如Cr-Mo钢，σw≈500 MPa）具有更高的疲劳强度。
Fatigue tests were carried out on nanocrystalline Ti- and Cu-based bulk metallic glasses (BMGs) for which there are still no reports on fatigue strength. Test alloy rods with a diameter of 2 mm were prepared in nanocrystalline Ti41.5Zr2.5Hf5Cu42.5Ni7.5Si1 at% and Cu60Zr30Ti10 at% systems by copper mold casting. Nanocrystals were dispersed in the metallic glassy phase in both BMGs. The tensile strength (σB) in the nanocrystalline Ti- and Cu-based BMGs were 2.04 GPa and 2.00 GPa, and Young' s modulus were 95 GPa and 114 GPa, respectively. The test specimens were machined to hourglass shape type (the radius in axial direction; 4.45 mm, the minimum diameter; 0.9 mm), and after machining the specimen surfaces were electropolished by 50~100 μm. The specimens were tested at a stress ratio of 0.1 and a frequency of 5-8 Hz. The fatigue limit (σw) (half a total stress amplitude) and fatigue ratio (σw/σB) in the nanocrystalline Ti- and Cu-based BMGs showed very large values (Ti-based alloy; 806 MPa and 0.40, Cu-based alloy; 490 MPa and 0.25). This experimental result indicated a possibility that the nanocrystal dispersed BMGs have higher fatigue strength than the high strength crystalline alloys with high fatigue strength (e.g. Cr-Mo steel, σw≈500 MPa).