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钨酸铅（ＰｂＷＯ４）晶体是一种新型的闪烁材料，它被广泛地应用于高能物理、核医学等领域，例如，西欧核子研究中心的大型强子对撞机工程就将钨酸铅闪烁晶体作为建造其探测器用的首选材料。钨酸铅晶体机械性能较差、脆性大、易解理、抗热震性差、易开裂。在高能物理上应用的晶体要求尺寸大、重量重，对晶体的加工精度要求也很高。为了确保晶体的加工精度，首先要严格控制晶体的平面度和磨抛前的最小加工余量。为了达到这一要求，在该晶体切割时的定位非常重要。对晶体定位我们是采用冷胶粘和加保护层的方法进行的，即将晶体、玻璃垫块（作保护层）及夹具在冷态下进行胶粘，晶体和玻璃垫块进行同步切割，并控制切割时玻璃层的切割深度，一般以０．５～１ｍｍ为宜，这样既确保锯片切割时的刚性和最佳切割速度，同时也保证了晶体切割面边缘的完整性，在切割２ｍｍ左右薄片晶体时也不会产生崩边现象，一般边缘崩角≤０．１ｍｍ（在允许倒角范围内）。采用冷态胶粘法定位可以避免由热胶法产生的热冲击和热应力，操作十分简便，一般需几分钟就可完成。钨酸铅晶体研磨和抛光是使晶体达到尺寸精度和表面粗糙度的要求。在晶体研磨抛光时除选用合适的磨料、粒度及均匀度外，还要注意磨盘直径、盘面材质、盘面平?
Lead tungstate (PbWO4) crystal is a new type of scintillation material, which is widely used in high-energy physics, nuclear medicine and other fields. For example, the Large Hadron Collider at the Western European Nuclear Research Center As the material of choice for the construction of its detector. Lead tungstate crystal mechanical properties are poor, brittle, easy cleavage, poor thermal shock resistance, easy to crack. Crystals used in high-energy physics require large size, heavy weight, and high requirements for crystal processing accuracy. In order to ensure the accuracy of the crystal processing, we must first strictly control the flatness of the crystal and grinding before throwing the minimum allowance. In order to meet this requirement, positioning during the crystal cutting is very important. The crystal positioning we are using cold glue and protective layer of the method, the crystal, the glass pad (for the protective layer) and the fixture in the cold state of adhesive, crystal and glass blocks for simultaneous cutting, and control Cutting glass layer cutting depth, generally 0.5 ~ 1mm is appropriate, so as to ensure the rigidity and cutting the blade cutting the best cutting speed, but also to ensure the integrity of the edge of the crystal cutting surface, in the cut 2mm or so slices Crystals will not produce chipping phenomenon, the general edge chipping ≤ 0.1mm (in the allow chamfer range). The use of cold gluing method to avoid thermal shock and thermal stress generated by the thermal glue method, the operation is very simple and generally takes a few minutes to complete. Lead tungstate crystal grinding and polishing is the crystal to achieve dimensional accuracy and surface roughness requirements. In the crystal grinding and polishing in addition to the selection of the appropriate abrasive, particle size and uniformity, but also pay attention to the disc diameter, disc surface material, disk surface flat?