Selective laser melting is able to produce complicated functional components. However, it may not simultaneously fulfill the diverse requirements of different parts of a component using uniform process parameters. Gradient processing based on the process parameters is proposed to realize the localized property design. An industrial valve body in a typical hydraulic valve was presented as a case study to demonstrate this concept. Lightweight design was first executed. Then, an experimental study was performed to investigate the influence of the laser power and exposure time on several properties, including the density, hardness, tensile strength, and tribological performance. Based on the specific property requirements of the shell, the fluid passages, and the contact surfaces of the valve body and electrical energy savings of the SLM process, three sets of process parameters were then selected to correspondingly fabricate different parts of the valve body. Results showed that the optimized valve body satisfied the relative density requirement of the shell as well as the yield strength and hardness requirements of the fluid passage. Moreover, compared with a solid valve body fabricated using a single set of default process parameters, the gradient processing leads to reductions from 3.5% to 51.8% in coefficients of friction in different working conditions, and a 4.8% reduction in the electric energy consumption. The lightweight design also contributes to a 21.8% reduction in the weight and a 22.9% reduction in the electric energy consumption. The optimized hydraulic valve also had functional characteristics that were comparable with those for the corresponding conventionally processed valve. This gradient processing was supported by design for property, a valuable technique for integrated design and manufacturing of functional gradient components.

中文翻译：

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选择性激光熔制液压阀体的局部特性设计与梯度处理。

选择性激光熔化能够产生复杂的功能组件。但是，它可能无法使用统一的过程参数同时满足组件不同部分的各种要求。提出了一种基于过程参数的梯度处理方法，以实现局部特性设计。作为案例研究，介绍了典型液压阀中的工业阀体，以证明这一概念。轻量级设计首先执行。然后，进行了一项实验研究，以研究激光功率和曝光时间对几种特性的影响，包括密度，硬度，拉伸强度和摩擦学性能。根据壳体，流体通道和阀体的接触面的特定性能要求以及SLM工艺的电能节省，然后选择三组工艺参数，以相应地制造阀体的不同部分。结果表明，优化后的阀体满足了壳体的相对密度要求以及流体通道的屈服强度和硬度要求。此外，与使用一组默认过程参数制造的固体阀体相比，梯度处理可在不同工作条件下将摩擦系数从3.5％降低至51.8％，电能消耗降低4.8％。轻巧的设计还有助于减少21.8％的重量和减少22.9％的电能消耗。优化的液压阀还具有与相应的常规处理阀相当的功能特性。该梯度处理得到了属性设计的支持，这是用于集成设计和制造功能性梯度组件的宝贵技术。