Volume production method of pressureless sintering boron carbide ceramic bullet-proof sheets

Abstract

The invention discloses a volume production method of pressureless sintering boron carbide ceramic bullet-proof sheets. The volume production method comprises the following steps: (1) putting various raw materials in material mixing and pulping equipment according to a formula proportion, wherein the raw materials are composed of a solid material A and a liquid material B, the material A comprises the following components in percentage by weight: 75-97wt% of boron carbide powder, 0-15.0wt% of sintering aids, 1.0-12.0wt% of carbon source, 0.5-6.0wt% of adhesive, and 0.5-6.0wt% of dispersant, and the sum of the percentages by weight of the components is 100%; the material B is deionized water; mixed ball milling or high speed stirring is performed on the material A and the material B to prepare a sizing agent, wherein the solid content of the sizing agent is 30-70 wt%; the sintering aids are one or more of nanometer level to micrometer level ZrC, TiC, SiC, AlN and TiB2. The method has the advantages of high yield of a single furnace, high degree of automation, non grinding processing of products, low cost and suitability for mass production, and low-cost and stable mass production is achieved.

Description

Technical field: [0001] The invention relates to a batch production method of pressureless sintered boron carbide ceramic bulletproof sheets. Background technique: [0002] In the field of national defense, bulletproof ceramic materials mainly include boron carbide (B 4 C), silicon carbide (SiC) and aluminum oxide (Al 2 o 3 ) three kinds, of which B 4 C has the lightest weight, high specific modulus, and good ballistic performance. It is the bulletproof ceramic material with the best comprehensive performance. However, because the pressureless sintering preparation process has not been solved for a long time, they are all prepared by hot pressing sintering method at present, and the cost and price are very expensive. Because of the high price, currently B 4 C Bulletproof ceramics are only used in the high-end protection market, such as the protection systems of helicopters, submarines, assault boats and fighters. Existing information shows that boron carbide has been w...

AI Technical Summary

Problems solved by technology

However, the added phenolic resin must be cracked and volatilized during the pressureless sintering process.

If large-scale and multiple sintering is carried out, a large amount of resin cracking products will seriously affect the performance of the pressureless sintering furnace, and normal sintering cannot be guaranteed

In this way, there are the following disadvantages: (1) carbonaceous insulation layers such as carbon felt in the sintering furnace will be corroded by a large amount of pyrolysis products, and the thermal insulation performance will deteriorate sharply; It is easy to get stuck and difficult to clean, and cannot guarantee the stable operation of the vacuum pump; (3) During the sintering high-temperature stage, stop vacuuming and fill in argon to protect the sintering, but the furnace (specifically refers to the carbonaceous insulation material and the inner wall of the furnace cooling layer) The residual pyrolyzate generates a large amount of gas, which causes the pressure in the furnace to rise rapidly, resulting in drastic fluctuations and deviations in the temperature data measured by the infrared temperature measurement system, making it impossible to obtain the true temperature in the furnace

The above three aspects are major defects that cannot be avoided by this method, which will inevitably lead to the failure of large-scale and multi-batch sintering of boron carbide, and cannot carry out stable production.