对于精密铸件，在其的学习上，前面已经开始进行了，主要是因为它是网站关键词之一，所以，要有全面了解，因此其学习工作应尽早进行。由于，其所包含的知识内容很多，而仅仅通过几篇文章无法完成，所以，不如来继续进行下去，这样，既可以让大家受益，又可以尽快完成这一工作，可谓是一举两得。
For precision castings, the learning process has already begun, mainly because it is one of the keywords on the website. Therefore, it is necessary to have a comprehensive understanding, so its learning work should be carried out as soon as possible. Because it contains a lot of knowledge and cannot be completed through just a few articles, it is better to continue, which can benefit everyone and complete the work as soon as possible. It can be described as killing two birds with one stone.
1.怎样，才算是合格的精密铸件？
1. What constitutes a qualified precision casting?
精密铸件的合格标准，是为：铸件表面没有粘砂氧化皮、飞边以及铸瘤等。如果在加工面上有表面缺陷的话，那么深度不能大于2mm。如果是在非加工面上的话，则深度不能超过1mm。此外，在其所有部位上，不能有线状缺陷和裂纹。满足上述这些条件，精密铸件才能算是合格的。
The qualification standard for precision castings is that the surface of the castings is free of sand scale, flash, and casting nodules. If there are surface defects on the machined surface, the depth cannot be greater than 2mm. If it is on a non machined surface, the depth cannot exceed 1mm. In addition, no linear defects or cracks are allowed on all parts. Only when these conditions are met can precision castings be considered qualified.
2.精密铸件进行回火，是在热处理中吗？
Are precision castings tempered during heat treatment?
精密铸件，其进行回火的话，一般是在热处理中的。其主要目的，是为了来改善铸件的一些性能，从而来提高其的使用性能和效果。因此，在材料选用和成形工艺的选择上，要做到合理，这样才行。
Precision castings, when tempered, are generally subjected to heat treatment. The main purpose is to improve some properties of castings, thereby improving their performance and effectiveness. Therefore, in the selection of materials and forming processes, it is necessary to be reasonable.
3.为何精密铸件可以是薄壁铸件？以及，其鼓包和漏铁水的原因是什么？
Why can precision castings be thin-walled castings? And what are the reasons for its bulging and molten iron leakage?
精密铸件，其可以是薄壁铸件的原因，是因为在精密铸造过程中，其模壳是高温预热的，而且浇注时，金属的凝固速度比较慢，所以，其可以是薄壁铸件。至于，精密铸件鼓包和漏铁水，在具体原因上，可能是铸件本身有问题，比如其模壳强度不够，或者是所使用的粘接剂有问题，从而导致了上述问题。
The reason why precision castings can be thin-walled castings is that during the precision casting process, their mold shells are preheated at high temperatures, and the solidification speed of the metal is relatively slow during pouring, so they can be thin-walled castings. As for bulging and molten iron leakage in precision castings, the specific reason may be that there are problems with the casting itself, such as insufficient mold shell strength, or a problem with the adhesive used, resulting in the above problems.
