In situ fabrication of TiC-NiCr cermets by selective laser melting
In situ fabrication of TiC-NiCr cermets by selective laser melting
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DOI：
10.1016/j.ijrmhm.2019.105171
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发表时间：
2020-02-01
影响因子：
3.6
通讯作者：
Berto, Filippo
中科院分区：
文献类型：
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作者：
Aramian, Atefeh;Sadeghian, Zohreh;Berto, Filippo
研究了选择性激光熔化 (SLM) 过程中 TiC-NiCr 金属陶瓷的原位合成。通过球磨工艺制备由 Ti、C 和 Ni80Cr20 固溶体组成的粉末混合物，以获得 TiC-40 wt% NiCr 的标称成分。将原料粉末用高能球磨机研磨7小时。在三种扫描速度下应用SLM工艺，并评估输入能量密度对所得样品的相形成、微观结构和硬度的影响。通过场发射电子显微镜 (FESEM) 研究了原位制造的金属陶瓷粉末的形貌和微观结构，并通过 X 射线衍射 (XRD) 研究了 SLM 过程中的结构演变。结果表明，即使在相对较低的能量密度下，SLM过程中也可以合成TiC，并且TiC相的形成机制受到输入能量密度的影响。随着能量密度从138.7 Jmm(-3)增加到346.7 Jmm(-3)，样品的相对密度从88.24%增加到98.53%。采用最大能量密度346.7 Jmm(-3)的SLM工艺制备的样品显示出最高的平均显微硬度值1289 HV。
In situ synthesis of TiC-NiCr cermets during selective laser melting (SLM) was investigated. Powder mixture consisting Ti, C and Ni80Cr20 solid solution was prepared by milling process to attain the nominal composition of TiC-40 wt% NiCr. Feedstock powder was milled for 7 h by a high energy ball mill. SLM process was applied at three scanning speeds and the effect of input energy density on phase formation, microstructure and hardness of resultant samples was evaluated. Morphology of the powders and microstructure of in situ fabricated cermets were investigated by field emission electron microscopy (FESEM), and structural evolution during SLM was studied by X-ray diffractometery (XRD). The results showed that TiC can be synthesized during SLM process even at relatively low energy densities and the formation mechanism of TiC phase is affected by the input energy density. Relative density of the samples increased from 88.24% to 98.53% with increasing the energy density from 138.7 to 346.7 Jmm(-3). The sample fabricated by SLM process using the maximum energy density of 346.7 Jmm(-3)showed the highest mean microhardness value of 1289 HV.