不同WC含量下WC/Cu复合材料弹性模量实验研究

Experimental study on the elastic modulus of WC/Cu composite material with different WC content

为了研究数字图像相关方法运用于小试样下WC/Cu复合材料弹性模量测定的准确性,采用粉末冶金法制备出了WC含量不同的WC/Cu复合材料,对试件表面用白漆配合碳粉方法进行制斑,并在万能材料试验机上进行拉伸实验,用CCD相机记录其散斑图。对记录的散斑图进行相关运算,并通过畸变校正理论校正位移计算结果,计算出小应变范围内WC/Cu复合材料的应力应变曲线,得到弹性模量;与传统电测方法结果进行对比,数据吻合较好。结果表明,采用数字图像相关方法和小试件制斑方法运用于WC/Cu复合材料弹性模量的测定是较为精确可靠的。

In order to study the accuracy of determination for elastic modulus of WC/Cu composites by digital image correlation method, WC/Cu composites with different WC content were prepared by powder metallurgy method. On the surface of specimens speckles were made by white paint with carbon powder. The tensile tests of these specimens were made in the universal material testing machine. Meanwhile the speckle figures were recorded by CCD camera. Correlation calculation was performed for the recorded speckle figures. And the calculation results were corrected according to the distortion correction theory. Then the stress-strain curve and elastic modulus of WC/Cu composites under small strain were given. The experimental results are in accordance with the results got by traditional electrical measurement. That means the measurement of elastic modulus of WC/Cu composites by digital image correlation applied to the small samples is correct and reliable.