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ＰｂＷＯ４闪烁晶体由于兼具成本低廉和性能优良的特点，已被确定为建造西欧大型强子对撞机的首选晶体，９５年至９８年为其Ｒ＆Ｄ阶段。根据有关的设计要求，ＰｂＷＯ４晶体冷加工后的尺寸应为２０．５×２０．５×２３０×２３．８×２３．８ｍｍ３。为此，生长的晶体毛坯尺寸应不小于３５×２５０ｍｍ３。生长如此大尺寸的ＰｂＷＯ４晶体，首先遇到的问题便是大尺寸晶体的开裂问题。ＰｂＷＯ４晶体较其它晶体（如Ｂｉ４Ｇｅ３Ｏ１２）容易开裂，有的被溅上少许冷水时便会开裂，甚至有的放于室内也会自然开裂。ＰｂＷＯ４晶体的开裂，主要发生在下降和冷却过程中，此外，冷加工（尤其是切割）过程中也常发生开裂现象。ＰｂＷＯ４晶体开裂的表现有４种：（１）横向层状似的断裂；（２）纵向长裂纹；（３）沿解理面［（１０１）和或（０１１）面］的开裂；（４）无规则的碎裂。ＰｂＷＯ４是ＰｂＯ和ＷＯ３摩尔比为１∶１的反应产物。ＰｂＷＯ４是固液同成分化合物，容许的组分偏离量很小，约±０．００５，若原料配比或熔体局部偏离化学计量比时，晶体易包容另相物———Ｐｂ２ＷＯ５或ＷＯ３。冷却过程中另相物发生多次相变（Ｐｂ２ＷＯ５：β→α；ＷＯ３：δ→γ→β→α），使晶体中出现微裂纹，?
The PbWO4 scintillation crystal has been identified as the crystal of choice for the construction of the large Hadron Collider in Western Europe due to its combination of low cost and high performance, with its 95-98 R & D phase. According to the relevant design requirements, the size of PbWO4 crystal after cold working should be 20.5 × 20.5 × 230 × 23.8 × 23.8mm3. To this end, the growth of the crystal blank size should not be less than 35 × 250mm3. The first problem encountered in growing PbWO4 crystals of such large size is the cracking of large-size crystals. PbWO4 crystal than other crystals (such as Bi4Ge3O12) easy to crack, and some will be splashed on a little cold water will crack, and even some will naturally cracked indoors. Cracking of PbWO4 crystals occurs mainly during descent and cooling, and in addition, cracking often occurs during cold working (especially cutting). There are four manifestations of PbWO4 crystal cracking: (1) transverse lamellar fractures; (2) longitudinal long cracks; (3) cracking along cleavage planes [(101) and No rules of fragmentation. PbWO4 is a reaction product of PbO and WO3 in a molar ratio of 1: 1. PbWO4 is a solid-liquid with the composition of compounds, the allowable deviation of the components is small, about ± 0.005, if the raw material stoichiometry or melt partial stoichiometry, the crystals easily contain another phase - Pb2WO5 or WO3. During the cooling process, several other phase transitions occur (Pb2WO5: β → α; WO3: δ → γ → β → α), causing microcracks in the crystal.