Correlation between microstructure and residual stress in the additively manufactured products using advanced experimental characterizations

使用先进的实验表征，了解增材制造产品中微观结构和残余应力之间的相关性

• 批准号: 533273-2018
• 负责人: NUÑO, Natalia
• 金额: $ 1.82万
• 依托单位: École de technologie supérieure
• 依托单位国家: 加拿大
• 项目类别: Engage Grants Program
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=661078
• 关键词: Correlation; between; microstructure; residual; stress

The concept of additive manufacturing (AM) in metallic materials such as steels, titanium alloys, and**biocompatible metals has gained enough attention to fabricate parts from easy to complex shape and geometry**more interestingly as semi-final or final products. The huge benefit from AM processes is to print the complete**shape of product in one step in contrary to conventional manufacturing processes where several steps are**required. The process has been developed over a few decades and it has become possible to produce 100%**dense bulk materials. In some industries such as marine industry and biomedical industry, certified products are**being fabricated. However, the mechanical properties may not meet the expectations in service due to complex**microstructure formed during AM processes. Due to repeated multiple thermal cycles induced by the**liquidation and solidification cycles applied to fabricate additive manufactured (AMed) products, different**level of recovery, local plastic deformation and structural discontinuities can be found in parts. As-fabricated**products own higher ultimate strength compared to their conventional versions but they show lower ductility**together with highly textured grains. This causes premature failure during mechanical evaluation. Therefore,**deep mechanical and metallurgical investigations are required to improve the part microstructures by**identifying the micro-mechanisms responsible for early failure and the solutions to improve mechanical**properties. The main objective of this project is described in the above explained context and aims to develop**an empirical model predicting the relationship between microstructural heterogeneities, residual strains**accumulated in the microstructure and resulted mechanical properties.

在金属材料（例如钢，钛合金和**生物相容性金属）等金属材料中的添加剂制造（AM）的概念引起了足够的关注，可以更有趣地将部分从易于到复杂的形状和几何形状**制造为半决赛或最终产品。 AM流程的巨大好处是，与传统的制造过程相反，在需要几个步骤**的传统制造过程中，打印完整的产品形状。该过程已经开发了几十年，并且有可能生产100％**密集的散装材料。在某些行业（例如海洋行业和生物医学行业）中，正在制造经认证的产品。但是，由于AM过程中形成的复杂**微观结构，机械性能可能无法满足服务期望。由于被施加在制造添加剂（AMED）产品的**清算和固化周期引起的重复多个热循环，因此可以在各个部分中找到不同的**恢复水平，局部塑性变形和结构性不连续性。与传统版本相比，使用的**产品具有更高的最终强度，但它们显示出较低的延展性**以及高质感的谷物。这会导致机械评估期间过早失败。因此，**需要进行深层机械和冶金研究，以通过**确定导致早期失败的微型机制以及改善机械**特性的解决方案来改善零件微观结构。该项目的主要目的是在上述上下文中描述的，旨在开发一个经验模型，以预测微结构异质性，残留菌株**在微观结构中积累和产生的机械性能之间的关系。