Ceramic Shot-Peening of a Landing Gear Component

起落架部件的陶瓷喷丸

• 批准号: 538023-2019
• 负责人: Liu, Rong
• 金额: $ 1.82万
• 依托单位: Carleton University
• 依托单位国家: 加拿大
• 项目类别: Engage Grants Program
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=680341
• 关键词: Ceramic; Shot; Peening; Landing; Gear

Shot peening is a cold working process in which the surface of a structural part is bombarded with small spherical medium called shot. The shots cause plastic deformation of the metal surface, which results in high compressive residual stresses in the area right beneath the dents. Since fatigue cracks generally originate at the surface of a part, compressive stresses induced by shot peening provide considerable increase in the part life.Landing gear flange pins are traditionally shot-peened by steel shots. However, the steel shots leave residue such as particle embedment, which could be detrimental to the service life of the pins. Also, the overall process using steel shots is lengthy. The most important is that during the high impact bombardment, the spherical shaped steel shots are plastically deformed (change the shape) and are not reusable. Therefore, the industry is trying to adopt ceramic shots that are not only reusable, but also give smoother surface finish and very low level of particle embedment/contamination.The objective of the proposed research is to investigate the possibility of replacing steel shots with harder ceramic shots. The surface quality after ceramic shot peening will be determined by measuring the roughness profile, the microstructure at the peened interface will be studied, and the residual stress will be measured from surface to the center of the specimen by XRD and stress profiles will be generated. The mechanical properties of the peened surface will be investigated via micro-indentation hardness and tensile testing, which will be compared with the unpeened specimen data.

Shot Peening是一个寒冷的工作过程，其中结构部分的表面被称为Shot的小球形介质轰炸。这些镜头会导致金属表面的塑性变形，从而导致凹痕下方的区域高压残留应力。由于疲劳裂纹通常起源于零件的表面，因此射击式引起的压缩应力可在零件寿命上大大增加。传统上，钢制齿轮法兰引脚被钢射击击中。但是，钢镜头留下了残留物，例如颗粒嵌入，这可能不利于引脚的使用寿命。同样，使用钢镜头的整体过程很长。最重要的是，在高冲击轰击期间，球形钢镜头被塑性变形（改变形状），并且不可重复使用。因此，该行业正试图采用不仅可以重复使用的陶瓷镜头，而且还可以使表面效果更平滑，并且颗粒嵌入/污染水平非常低。拟议的研究的目的是研究用更硬的陶瓷镜头更换钢镜头的可能性。陶瓷射对后的表面质量将通过测量粗糙度曲线，将研究剥离界面处的微观结构来确定，并将通过XRD从表面到样品中心测量残留应力，并产生应力轮廓。剥离表面的机械性能将通过微观识别硬度和拉伸测试研究，这将与未经未受的标本数据进行比较。