亞洲國產一區在線觀看_国产床戏无遮挡免费观看网站_在线国产一区a一级毛片_诱人的巨大双乳按摩_av免费午夜影院_日韩无码影音资源站_黄片免费国产颜值女生_女人三a级毛片视频

Key points in sample preparation:

1、Cutting

Compared with other metals, titanium has a relatively low thermal conductivity, so water cooling must be used when cutting the sample to prevent local overheating. In addition, the cutting rate and feed rate of the cutting blade should be reduced. Materials are divided into soft and hard. In addition to silicon carbide cutting blades, resin diamond cutting blades with relatively weak bonding strength can also be used for cutting.

                                                       Silicon carbide resin cutting blade                                                                               Resin diamond cutting blade

2、Mounting

Titanium and titanium alloys are generally mounted cold. In addition to the decomposition of the stable β phase, hot mounting may also produce hydrogen contamination, because hydrogen in the mounting material may diffuse into the sample under hot conditions, especially for samples with a high α phase content. Since the solubility of hydrogen in the α phase is extremely low, the solubility increases when the temperature rises, and the solubility decreases when cooling, resulting in the precipitation of fine and dispersed titanium hydride.

                                                           Titanium alloy mounting                                                                                  MC003 vacuum-free clear cold mounting kit

3、Grinding and polishing

Titanium alloys are usually prepared by mechanical polishing, which requires good control of pressure and speed.

The final polishing is usually repeated for a short period of time.

Since high-purity titanium is prone to surface deformation, electrolytic polishing is generally used to avoid the formation of a metamorphic layer.

The above recommended parameters are taken from: Preparation method of Ф30 mm titanium alloy sample with Ф250 mm working plate on automatic grinding and polishing machine Smoothneer-6.