建立了TC4钛合金材料的疲劳裂纹萌生寿命的预测模型,并通过试验验证了此模型在预测TC4钛合金材料疲劳裂纹萌生寿命时的可行性.基于裂纹萌生的细观位错模型,采用Tanaka-Mura的开裂寿命公式,考虑了表面粗糙度,提出了分析TC4钛合金材料疲劳裂纹萌生的有限元模型,并通过实验验证仿真模型的有效性.结果 表明:模型裂纹萌生形式在不同载荷水平下存在差异,高应力水平状态下,模型除了主裂纹的萌生扩展还伴有大量独立微裂纹,裂纹密度大,而在低应力水平状态下,模型存在少量独立微裂纹,裂纹密度小.

In the CATIA V5, creating a model of texts needs to be converted by using an intermediate format such as DXF. This operation is inconvenient, and the surface quality is not high. Through the study of TrueType fonts, it is found that Bezier curves used to describe glyphs are very common in 3D modeling software. In response to this feature, this paper uses CATIA V5 secondary development technology to read the text outline by reading the TrueType font-related API functions, and then quickly draw the sketch of the text outline in CATIA V5 to create a 3D model. The method was used to prepare the corresponding tools for the part design and achieved good results.