Zr基非晶合金在拉伸条件下流变特征与本构方程  

The Constitutive Equation and Rheological Characteristics of Zr-Based Amorphous Alloy Under Tensile Experiments

作　　者：邱克强[1] 于向男 张丹[1] 任英磊[1] 

机构地区：[1]沈阳工业大学材料科学与工程学院,辽宁沈阳110870

出　　处：《铸造》2015年第12期1218-1221,1225,共5页Foundry

基　　金：国家重点基础研究发展计划(2011CB606301)

摘　　要：非晶合金的本构方程是其微小元器件成形的基础,由于压缩实验容易实现,因此目前多数研究是以这种方法建立非晶合金本构方程的,而系统地以拉伸实验确立非晶合金的本构方程还未见报道。文中采用铜模铸造法制备了(Zr_(33.2)Ti_(36.1)Ni_(5.8)Be_(24.9))_(91)Cu_9大块非晶合金,分别在不同温度和应变速率下,在非晶合金的过冷液相区对其进行拉伸实验。通过模型和数据分析,建立了非晶合金在拉伸条件下的Maxwell-Pulse本构方程。分析表明,在应变速率为0.5×10^(-3)s^(-1),温度高于622 K,或在622 K,应变速率低于0.5×10^(-3)s^(-1)时,非晶合金具有牛顿流变特征,反之为非牛顿流变。以样品在拉伸时的缩颈规律为基础,通过引入几何修正因子,考虑了缩颈对应力-应变关系的影响,使得Maxwell-Pulse本构方程可以较好的描述(Zr_(33.2)Ti_(36.1)Ni_(5.8)Be_(24.9))_(91)Cu_9非晶合金在过冷液相区的拉伸变形行为。The constitutive equation is the fundamental for micro-size of machine parts of amorphous alloys. Therefore many researches are focused on the construction of constitutive equation by using compressor experiments because it is easy to realize. There is almost no systematical investigation on the construction of the constitutive equation based on tensile experiments. In this paper, bulk amorphous samples with composition of （Zr33.2Ti36.1Ni5.8Be24.9）91Cu9 were fabricated by using copper mold casting method. Tensile experiments under different strain rates and temperatures were conducted for the samples in the supercooled liquid region of the amorphous alloy. The Maxwell-Pulse constitutive equation under tensile condition was established by model and data analysis. The analyses indicate that the amorphous alloy presents rheological characteristics of Newton when the temperature is above 622 K and strain rate of 0.5×10^-3s^-1, or the strain rate is below 0,5×10^-3s^-1and temperature of 622 IC Conversely the amorphous alloy presents the non-Newton＇s rheology. The necking of the samples during tensile tests was considered by inducing geometric factor, which makes the Maxwell-Pulse constitutive equation can be better to describe tensile deformation behavior of （Zr33.2Ti36.1Ni5.8Be249）91Cu9 amorphous alloy in the supercooled liquid region.

关 键 词：非晶合金 过冷液相区 拉伸实验 本构方程 缩颈 几何因子 应力过冲 稳态流动 

分 类 号：TG139.8[一般工业技术—材料科学与工程]