论文标题
对添加剂制造的不锈钢和AL-12SI粉末的导热率的数值模拟
Numerical simulation of thermal conductivity of stainless steel and Al-12Si powders for additive manufacturing
论文作者
论文摘要
已经开发了一种部分融化的粉末床的三维模型，其颗粒随机分布在大小和空间坐标中。对真空，空气和氩气中不锈钢AISI 316L和AL-12SI粉末中温度分布的数值模拟已进行了分析，以分析多孔培养基中不稳定的热传递。数值模型表明，如果粉末（如不锈钢）（不锈钢）的粉末，传热的影响很大。在65 \％及以上的孔隙率水平上，传热的机理发生了巨大变化，并且导热性对文献中经常使用的孔隙率的线性依赖性变得不正确。讨论了合并系数和大小分布对粉末有效传热的影响。有效的热导率对孔隙率和合并系数的依赖性可用于增材制造应用。
A three-dimensional model of a partially melted powder bed with particles stochastically distributed in size and space coordinates has been developed. Numerical simulation of temperature distributions in stainless steel AISI 316L and Al-12Si powders in vacuum, air and argon has been performed to analyze unsteady heat transfer in a porous medium. The numerical model demonstrates a large effect of heat transfer through the gas phase in case of powders with low thermal conductivities like stainless steels. At the porosity level of 65\% and above, the mechanism of heat transfer drastically changes and a linear dependence of thermal conductivity on porosity frequently used in literature becomes incorrect. The effects of the consolidation coefficient and size distribution on effective heat transfer in powders are discussed. The obtained dependencies of the effective thermal conductivity on porosity and the consolidation coefficient could be used in additive manufacturing applications.
