摘要:
采用铜模吸铸法在三元Zr56Co28Al16和四元Zr56Co28?xCuxAl16(x=2,4,5,6,7,摩尔分数,%)非晶合金中形成大块金属玻璃(BMGs).本研究主要目的是找到四元ZrCo(Cu)Al合金中形成大块金属玻璃的最优成分,并提高母合金的塑性.采用X射线衍射(XRD)技术、透射电镜(TEM)和差示扫描量热法(DSC)研究非晶合金的结构及其玻璃形成能力(GFA).此外,利用压缩试验、显微硬度、纳米压痕和扫描电镜(SEM)讨论塑性提高的可能机制.含铜合金中玻璃形成能力最强的是Zr56Co22Cu6Al16合金,与基体合金相似.此外,Zr56Co22Cu6Al16大块金属玻璃的塑性从基体合金的3.3%显著增加到6%.最后,结合铜和钴的正混合热,讨论合金塑性和GFA的变化.%The formation of bulk metallic glasses (BMGs) in the ternary Zr56Co28Al16 and quaternary Zr56Co28?xCuxAl16 (x=2, 4, 5, 6, 7, mole fraction, %) glassy alloys was investigated via the copper mold suction casting method. The main purpose of this work was to locate the optimal BMG-forming composition for the quaternary ZrCo(Cu)Al alloys and to improve the plasticity of the parent alloy. The X-ray diffractometry (XRD), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC) were used to investigate the glassy alloys structure and their glass forming ability (GFA). In addition, the compression test, microhardness, nano-indentation and scanning electron microscopy (SEM) were utilized to discuss the possible mechanisms involved in the enhanced plasticity achievement. The highest GFA among Cu-containing alloys was found for the Zr56Co22Cu6Al16 alloy, which was similar to that of the base alloy. Furthermore, the plasticity of the base alloy increased significantly from 3.3% to 6% for the Zr56Co22Cu6Al16 BMG. The variations in the plasticity and GFA of the alloys were discussed by considering the positive heat of mixing within Cu and Co elements.