Quartz crucible, also known as quartz sand crucible, is a crucible made by firing quartz sand. It has the advantages of high temperature resistance, corrosion resistance, and easy handling, so it is widely used in mineral mining, smelting, distillation, chemical industry, and modern industrial production, especially in the photovoltaic and semiconductor industries. Quartz crucible is an important container for extracting crystalline silicon. However, during use, quartz crucibles can sometimes rupture, causing significant losses to production.

So what are the reasons for the rupture of quartz crucibles?

1. Improper melting method

1.1 Secondary crystallization: When the upper silicon material melts and flows down along the inner wall of the quartz crucible to the bottom, if the bottom temperature is too low, the silicon material will undergo "secondary" crystallization. Silicon material undergoes expansion during "secondary" crystallization, and this expansion force will cause the quartz crucible to crack.

1.2 Leakage of silicon after bottom flipping: When the upper molten silicon liquid flows along the crucible wall to the bottom of the crucible, it will stick the bottom block material and quartz crucible together. When the upper silicon material is completely melted into a liquid, buoyancy is formed on the bottom block material. When the buoyancy is large enough to detach the unfinished block material from the bottom of the quartz crucible adhered to it, the crucible can often be pulled apart.

2. Improper melt temperature

Excessive temperature of the molten material will intensify the degree of crystallization in the crucible and increase the possibility of cracking. At high temperatures, the material of quartz crucibles is more prone to physical and chemical changes, leading to structural instability and increasing the risk of rupture.

3. Raw material issues

Excessive impurities in the raw materials or contamination during the cleaning and loading process can corrode the quartz crucible. In severe cases, molten silicon can penetrate into the inner layer of the crucible, causing structural damage and rupture of the crucible.

4. Graphite crucible issue

4.1 Insufficient thorough calcination of new graphite crucible: If a new graphite crucible is put into use without thorough calcination treatment, it will cause severe crystallization of the outer layer of the quartz crucible, increasing the risk of rupture.

4.2 Prolonged use of graphite crucible: Due to prolonged use, the original thickness of graphite crucible will be greatly reduced by oxidation degradation, which may affect its protective effect on quartz crucible and lead to its rupture.

5. Problems with the quartz crucible itself

5.1 Excessive force when placing quartz crucible: If excessive force is applied when placing quartz crucible, the bottom may be damaged and hidden cracks may occur, which may expand during the melting process and lead to rupture.

5.2 Impact of large pieces of silicon material during bottom material loading: If large pieces of silicon material hit the bottom of the quartz crucible during bottom material loading, hidden cracks may occur, which may also lead to subsequent rupture during the melting process.

5.3 Too much large material is loaded into the upper part of the crucible: When too much large material is loaded into the upper part of the crucible, material collapse may occur during the melting process, and the collapsed silicon material can easily break the bottom of the crucible, causing silicon leakage.

5.4 Damage to Quartz Crucible by External Forces: During production, packaging, transportation, or use, if quartz crucible is damaged by external forces, hidden cracks may occur, which are prone to rupture during the melting process.

6. Other factors

Improper operation: If the heating and cooling speed is too fast, it may cause thermal shock cracking.

Improper cleaning and maintenance: Using excessively strong corrosive solutions such as acid and alkali for cleaning, or applying excessive force during the cleaning process, may cause damage to the quartz crucible.

The reasons for the rupture of quartz crucibles are complex and diverse, involving multiple aspects such as melting methods, temperature control, raw material quality, graphite crucible condition, quartz crucible quality, and operation and maintenance.

Luverre Quartz manufactures and sells a wide range of high quality quartz glass, including quartz tubes, quartz plates, quartz rods, quartz windows, quartz crucibles, quartz boats, quartz flanges, quartz beakers, quartz glass instruments, and more. We can meet all kinds of customized requirements for quartz glass products.