Preparation method of crystallite glass with low expansion rate

Abstract

The invention relates to a preparation method of crystallite glass, in particular to a preparation method of crystallite glass with a low expansion rate. According to the specific technical scheme, the preparation method comprises the following steps: weighing glass raw material, evenly mixing the raw material and putting into a crucible; heating up to 1550 DEG C, carrying out heat preservation for 4h, cooling to 1450 DEG C and carrying out heat preservation for 1h; carrying out annealing treatment for 5h at the temperature of 680 DEG C to obtain base glass; and then carrying out coring and crystallization, wherein the coring temperature is 750 DEG C, the coring time is 1h, the crystallization temperature is 1075 DEG C, and the crystallization time is 1.5h. The production method provided by the invention is capable of effectively separating out cordierite and reducing the expansion factor, thus guaranteeing the performances of the crystallite glass.

Description

technical field

[0001] The invention relates to a method for preparing a glass-ceramic, in particular to a method for preparing a glass-ceramic with a low expansion rate. Background technique

[0002] MgO-A1 2 o 3 -SiO 2 The glass-ceramic has excellent high-frequency electrical properties, high mechanical strength, good thermal shock resistance and thermal stability, and has been widely used in electronics, aerospace, machinery and other fields. These superior properties are derived from cordierite (2MgO·2A1 2 o 3 ·5SiO2 2 ) The precipitation of the main crystal phase. The thermal expansion coefficient of cordierite is isotropic. As the temperature increases, it expands in the c-axis direction but contracts in the a-axis direction, resulting in zero volume expansion. Due to the complex crystallization process of this system, the precipitation of heterogeneous crystal phases will lead to the destruction of glass properties due to phase change. Contents of the inventi...

Examples

specific Embodiment approach

[0010] (1) Weigh glass raw materials, the weight percentage is, MgO15.2kg, Al 2 o 3 22.3kg, SiO 2 48kg, CaO2kg, B 2 o 3 2kg, Sb 2 o 3 0.5kg, ZnO 2 10kg;

[0011] (2) Mix the above raw materials and add them into the crucible, raise the temperature to 1550°C, keep it warm for 4h, then lower it to 1450°C and keep it warm for 1h;

[0012] (3) Then cast into a thin plate and anneal at 680°C for 5 hours to obtain the basic glass;

[0013] (4) The basic glass is then nucleated and crystallized. The nucleation temperature is 750°C, the nucleation time is 1h, the crystallization temperature is 1075°C, and the crystallization time is 1.5h.

[0014] The obtained glass-ceramic with a small expansion coefficient is 23.535×10 / ℃.

technical field

[0001] The invention relates to a method for preparing a glass-ceramic, in particular to a method for preparing a glass-ceramic with a low expansion rate. Background technique

[0002] MgO-A1 2 o 3 -SiO 2 The glass-ceramic has excellent high-frequency electrical properties, high mechanical strength, good thermal shock resistance and thermal stability, and has been widely used in electronics, aerospace, machinery and other fields. These superior properties are derived from cordierite (2MgO·2A1 2 o 3 ·5SiO2 2 ) The precipitation of the main crystal phase. The thermal expansion coefficient of cordierite is isotropic. As the temperature increases, it expands in the c-axis direction but contracts in the a-axis direction, resulting in zero volume expansion. Due to the complex crystallization process of this system, the precipitation of heterogeneous crystal phases will lead to the destruction of glass properties due to phase change. Contents of the inventi...

Examples

specific Embodiment approach

[0010] (1) Weigh glass raw materials, the weight percentage is, MgO15.2kg, Al 2 o 3 22.3kg, SiO 2 48kg, CaO2kg, B 2 o 3 2kg, Sb 2 o 3 0.5kg, ZnO 2 10kg;

[0011] (2) Mix the above raw materials and add them into the crucible, raise the temperature to 1550°C, keep it warm for 4h, then lower it to 1450°C and keep it warm for 1h;

[0012] (3) Then cast into a thin plate and anneal at 680°C for 5 hours to obtain the basic glass;

[0013] (4) The basic glass is then nucleated and crystallized. The nucleation temperature is 750°C, the nucleation time is 1h, the crystallization temperature is 1075°C, and the crystallization time is 1.5h.

[0014] The obtained glass-ceramic with a small expansion coefficient is 23.535×10 / ℃.