Interfacial thermal conductance of 7075 aluminum alloy microdroplets in contact with a solid at fast melting and crystallization
Interfacial thermal conductance of 7075 aluminum alloy microdroplets in contact with a solid at fast melting and crystallization
复制标题
DOI：
10.1088/2053-1591/ac859b
复制
发表时间：
2022-07
影响因子：
2.3
通讯作者：
A. Minakov;J. Morikawa;M. Ryu;E. Zhuravlev;C. Schick
中科院分区：
文献类型：
--
作者：
A. Minakov;J. Morikawa;M. Ryu;E. Zhuravlev;C. Schick
超快纳米量热法与高速红外热成像相结合，用于测量快速熔化（包括激光加热）过程中金属微滴与固体热接触的界面热导率（ITC）。红外热成像和膜纳米量热法用于测量铝合金（AA 7075）微滴（直径20 μm）在宽范围的加热和冷却速率（高达105 K s−1）下熔化和结晶期间膜/样品界面处的温差。这是首次使用这种新方法在如此高的加热和冷却速率下测量ITC。我们发现，在激光加热过程中的微滴的凝固过程中，界面温差达到约80 K。这一结果对于理解各种工业激光辅助过程具有重要意义。已经确定，在从合金的固相线温度到液相线温度的范围内的熔化期间，对于AA 7075微滴测量的ITC逐渐增加一个数量级。ITC在熔化过程中的这种不寻常行为对于理解和优化激光辅助增材制造工艺非常重要。
Ultrafast nanocalorimetry, in combination with high-speed IR thermography, is used to measure the interfacial thermal conductance (ITC) of the thermal contact of metal microdroplets with a solid during fast melting (including laser heating). IR thermography and membrane nanocalorimetry were used to measure the temperature difference at the membrane/sample interface during the melting and crystallization of aluminium alloy (AA7075) microdroplets (20 μm in diameter) over a wide range of heating and cooling rates (up to 105 K s−1). This is the first time ITC has been measured at such high heating and cooling rates with this new method. We found that the interfacial temperature difference reaches about 80 K during the solidification of microdroplets during laser heating. This result is significant for understanding various industrial laser-assisted processes. It has been established that ITC measured for AA7075 microdroplets gradually increases by an order of magnitude during melting in the range from the solidus temperature to the liquidus temperature of the alloy. This unusual behavior of ITC during melting can be important for understanding and optimizing laser-assisted additive manufacturing processes.