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试验与研究 DOI:10.11973/lhjy-wl240105
Zr Ti Cu Al 非晶态合金在四点弯曲加载模式下的
61
12
25
2
弯曲弹性极限
沈 勇,温井龙
(中国科学院 金属研究所,沈阳 110016)
摘 要:按照当前金属材料弯曲性能测试标准中推荐的跨厚比设计Zr 61 Ti 2 Cu 25 Al 12 非晶态合金的
弯曲试验,试样将发生大挠度弹性变形。经过推导证明,弯曲试样不发生大挠度弹性变形的跨厚比上
限取决于材料的弹性应变极限,锆基非晶态合金的弹性应变极限为2%,在四点1/4弯曲模式下不发
生大挠度弹性变形的跨厚比上限值为22。在保证小挠度变形的前提下,通过四点弯曲循环加载-卸
载试验,Zr 61 Ti 2 Cu 25 Al 12 合金试样最外表层发生初始剪切变形所对应的弯曲屈服应力约为1 760 MPa,
产生0.01%残余应变所对应的弯曲弹性极限σ p0.01 为2 040 MPa。
关键词: 非晶态合金;四点弯曲;弯曲弹性极限;跨厚比;大挠度弹性变形
中图分类号:TG115.5;TB31 文献标志码:A 文章编号:1001-4012(2024)08-0023-08
Flexural elastic limit of Zr Ti Cu Al amorphous alloy under four-point
25
12
2
61
bending loading mode
SHEN Yong, WEN Jinglong
(Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China)
Abstract: The bending test of Zr Ti Cu Al amorphous alloy was designed according to the span-thickness
61 2 25 12
ratio recommended in the current metal material bending performance test standard, and the specimen would undergo
large deflection elastic deformation. It was proved that the upper limit of the span-to-thickness ratio of the bending
specimen without large deflection elastic deformation depended on the elastic strain limit of the material. The elastic strain
limit of the zirconium-based amorphous alloy was 2%, and the upper limit of the span-to-thickness ratio without large
deflection elastic deformation in the four-point 1/4 bending mode was 22. Under the premise of ensuring small deflection
deformation, through the four-point bending cyclic loading and unloading test, the bending yield stress corresponding to
the initial shear deformation of the outermost surface of the Zr Ti Cu Al alloy sample was about 1 760 MPa, and the
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bending elastic limit σ corresponding to 0.01% residual strain was 2 040 MPa.
p0.01
Keywords: amorphous alloy; four-point bending; bending elastic limit; span-thickness ratio; large deflection
elastic deformation
非晶态合金(也称金属玻璃)在结构上具有原 称ZT1合金)具有较低的弹性模量(E=82.8 GPa)和
[5-6]
子排列长程无序、短程有序的特点 。相对于晶态 较高的拉伸屈服应力(1 600 MPa) ,弹性比能高达
[1]
15.0 MJ/m ,大约是普通弹簧钢的3~5倍,并且材料无
3
金属,非晶态合金具有高强度、高弹性应变极限等特
磁性,可用于制造微型片簧、膜片、挠性杆等高精密弹
点,因此非晶态合金具有较高的弹性比能,是一种理
性元器件。这些器件的服役工况多数近似为弯曲,工
想的新型金属弹簧材料 [2-4] 。具有高断裂韧度(K JIC =
程设计者需要知悉制备材料在弯曲载荷模式下的力学
130 MPa · m )的Zr 61 Ti 2 Cu 25 Al 12 非晶态合金(以下简 性能,如弯曲弹性极限、抗弯强度和弯曲弹性模量等。
1/2
通常,人们通过三点或四点弯曲试验获得“载
收稿日期:2024-04-15
荷-挠度”曲线,评价脆性或低塑性断裂材料试样的
作者简介:沈 勇(1976-) ,男,博士,副研究员, 主要从事材料
力学性能测试表征工作, yongshen@imr.ac.cn 弯曲性能。脆性断裂材料(如陶瓷、玻璃等)一般在
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