论文部分内容阅读
对Mg61Cu28Gd11块体非晶在其玻璃转变温度以下温度(325、350、375和400 K)等温退火1 h,用X射线衍射仪(XRD)、差热扫描量热仪(DSC)、纳米压痕仪、扫描电子显微镜(SEM)、显微维氏硬度计等分析研究了低温退火对其热稳定性、微区力学性能及变形的影响,并分析了塑性变形机理。结果表明,低温退火后非晶原子的短程有序性增加,非晶结构的稳定性变差,并在400K发生部分晶化。同时,在325～375 K范围内,显微硬度和弹性模量E随退火温度的升高而增大,塑性变形量Dn和最大压入深度Dmax减小;400 K退火后,由于少量析出的晶体相与压头下新产生的自由体积相互作用,合金抵抗变形能力减弱,显微硬度和弹性模量E降低,Dn和Dmax提高。
The Mg61Cu28Gd11 bulk amorphous alloys were annealed at temperatures below the glass transition temperature (325, 350, 375 and 400 K) for 1 h by X-ray diffractometry (XRD), differential scanning calorimetry (DSC) The effects of low temperature annealing on its thermal stability, mechanical properties and deformation of micro-zone were studied by SEM, SEM and micro Vickers hardness tester. The mechanism of plastic deformation was also analyzed. The results show that the short-range ordering of amorphous atoms increases after annealing at low temperature, the stability of amorphous structure deteriorates and partial crystallization occurs at 400K. At the same time, in the range of 325 ~ 375 K, the microhardness and elastic modulus E increased with the increase of annealing temperature, and the plastic deformation Dn and the maximum penetration depth Dmax decreased. After 400 K annealing, due to the small amount of precipitation The interaction of the crystal phase with the newly generated free volume under the indenter weakens the resistance to deformation of the alloy, decreases the microhardness and elastic modulus E, and increases Dn and Dmax.