Khaimovich Alexander, Erisov Yaroslav, Shishkovsky Igor
Engine Production Technology Department, Samara National Research University, 34 Moskovskoye Shosse, 443086 Samara, Russia.
Metal Forming Department, Samara National Research University, 34 Moskovskoye Shosse, 443086 Samara, Russia.
Materials (Basel). 2022 Jan 21;15(3):825. doi: 10.3390/ma15030825.
Functional Graded Structures and Functional Graded parts, made using dissimilar materials, are designed to provide specific properties to the final product. One of the most promising methods for manufacturing 3D Functional Graded objects is 3D laser cladding and/or direct energy deposition. However, the construction of graded and especially layered graded structures in the process of joining materials with different thermophysical properties under certain conditions is accompanied by the formation of cracks along the phase boundaries, which are a consequence of residual stresses and/or chemical segregations. The conditions for phase consolidation are macroscopic balancing of residual stresses in the region of the interface. In a broader sense, in the field of the interface, it is necessary to consider the thermodynamic equilibrium of the phases in connection with mechanical equilibrium. In this regard, the article proposed criteria for the thermodynamic affinity of phases in the area of the Functional Graded Structures interface, including the coefficients of thermal expansion and isobaric and isochoric heat capacities of the phases. Examples of cracking and the use of the obtained criteria are provided.
功能梯度结构和使用不同材料制成的功能梯度部件，旨在为最终产品提供特定性能。制造三维功能梯度物体最有前景的方法之一是三维激光熔覆和/或直接能量沉积。然而，在特定条件下将具有不同热物理性质的材料连接在一起的过程中，梯度结构尤其是层状梯度结构的构建会伴随着沿相界形成裂纹，这是残余应力和/或化学偏析的结果。相固结的条件是界面区域残余应力的宏观平衡。从更广泛的意义上讲，在界面领域，有必要结合机械平衡来考虑相的热力学平衡。在这方面，本文提出了功能梯度结构界面区域相的热力学亲和性标准，包括相的热膨胀系数以及等压和等容热容。文中提供了裂纹示例以及所获标准的应用情况。
