Development of metallic glass composite with zero-thermal expansion using negative thermal expansion materials and the evaluation of machinability

本研究的目的是将正负热膨胀材料相结合，开发出零热膨胀系数的非晶合金复合材料。采用火花等离子烧结（SPS）方法，在温度为270 k ~ 350k的863K条件下，成功烧结出了Fe_<43>Cr_<16>Mo_<16>C_<15>B_<10>的非晶金属玻璃（Fe_<43>Cr_<16>Mo_<16>C_<15>B_<10>）和抗钙钛矿氮化物Mn_3(Cu_<0.53>Ge_<0.47>) N，其玻璃化转变温度为Fe_<43>Cr_<16>Mo_<16>C_<15>B_<10>。Fe_<43>Cr_<16>Mo_<16>C_<15>B_<10>金属玻璃在过冷状态下的粘性流动使其能够在如此低的温度下烧结，而在SPS过程中，Fe_<43>Cr_<16>Mo_<16>C_<15>B_<10>金属玻璃保持了非晶态结构。在263 K-353K范围内，复合材料的热膨胀系数几乎为零。

Aim of this study is development amorphous alloy composite with zero thermal expansion coefficient by combining positive and negative thermal expansion materials. Metallic glass(amorphous) Fe_<43>Cr_<16>Mo_<16>C_<15>B_<10> and anti-perovskite nitride Mn_3(Cu_<0.53>Ge_<0.47>) N, which exhibits negative thermal expansion in a temperature range of 270 K-350K, were successfully sintered at 863K, which is equal to a glass transition temperature of Fe_<43>Cr_<16>Mo_<16>C_<15>B_<10> metallic glass, by spark plasma sintering(SPS) method. Viscous flow in a super-cooled state of Fe_<43>Cr_<16>Mo_<16>C_<15>B_<10> metallic glass enabled the sintering at such a low temperature, while amorphous structure of the Fe_<43>Cr_<16>Mo_<16>C_<15>B_<10> metallic glass was maintained during SPS process. The coefficient of thermal expansion of the composite exhibited almost zero in a range of 263 K-353K.