ZL303合金电磁热止裂后力学性能研究

利用自制的ZL-2超强脉冲放电装置对含有单边裂纹的ZL303合金试件进行电磁热止裂试验。通过微机控制电子万能试验机对止裂前后试件进行拉伸试验,并用SEM扫描电镜对断口进行观察,最后理论分析了受拉伸试件的应力强度因子。结果表明,电磁热止裂技术对ZL303具有良好的止裂效果;放电强化作用主要集中在裂尖附近,裂尖钝化形成焊口,裂尖处组织变细且强度提高,试件的抗拉强度平均提高了16.5%;电热应力强度因子削弱了拉应力所产生的应力强度因子,达到力学性能强化的效果。

Experimental Study on Mechanical Properties of ZL303 Alloy Subjected to Electromagnetic Thermal Crack Arrest

In this paper,electromagnetic thermal crack arrest experiment of ZL303 alloy specimen with unilateral crack was carried out by using a self-made ZL-2 super pulse discharge device.Tensile experiment of specimens before and after thermal crack arrest treatment was carried out based on computer controlled electronic universal testing machine.The fracture surface was observed by scanning electron microscope (SEM).Finally,stress intensity factor of tensile specimen was theoretically analyzed.Results show that the electromagnetic thermal arrest technique has a good effect on crack arrest of ZL303;The discharge enhancement effect is mainly concentrated near the crack tip;Crack tip passivation forms solder joint,and its microstructure becomes thinner and strength is improved.The tensile strength of specimen increases averagely up to 16.5％.The thermal stress intensity factor weakens the stress intensity factor produced by tensile stress,so,the enhancement effect of mechanical properties is achieved.