DAAO Industry Co., Ltd

Thermal Spray is technology for surface protection and strengthening. So-called thermal spray is to use certain hot source,such as electric arc,plasma arc,burning flame,to melt powder or wire metal and nonmetal into liquid or semi-liquid status, withthe help of flame flow force or additional high-velocity airflow atomization, to jet to the surface of the base materials, to form different coating layer with many functions.

The kinds of Thermal Spray Technology

According to the kinds of hot source, thermal spray technology can be divided into

Equipment of Thermal Spray

Equipments vary due to different methods. But based on the principals of thermal spray, the main equipments include welding gun, hot source, feeding unit of coating materials, controlling system and cooling system.

Thermal Spray Process

• Pre-treatment for surface of work piece: The matrix surface must be clean and rough in order to combine the coating materials and matrix.
• Pre-heat for the work piece: The purpose of pre-heat is to remove the moisture in the matrix surface to improve the touching temperature between spraying particles and work piece, thus to improve its combined strength；to reduce the stress because of heat expansion different to avoid the crack of the layer.
• Spraying: Certain method differs from the choice of spraying materials, work piece status, and the quality requirements for the coating.
• Coating layer after-treatment: Coating layer obtained can not be used directly, it must be treated several steps. For example, coating for erosion-resistant, the mini-hole on the coating layer must

Feature of Thermal Spray Technology

1. Due to the wide temperature rang of hot source, coating layer materials cover almost all solid engineering materials, such as metals, alloys, ceramic, ceremet, plastic, and its complex, and give, matrix many functions(i.e：wear-resistant, erosion-resistant, anti-high temperature, anti-oxidation, insulation)

2. The temperature of the matrix surface is less and easy to control during spraying, thus spraying can be applied o all kinds of materials(metals, ceramics etc.). It does not affect the tissue and performance to the matrix, and deformation is also very less.

3. With simple equipment and flexible operating, it can be used for not only the huge area of big-size work piece, but also the local specified place of the work piece; applied not only the indoor, but also outside operation.

4. Steps of spraying is less, operating time is short, so it is effective and economical. It is a good way to save precision metals and energy, to improve quality, to prolong product life spray, to lower cost, and thus widely used in all kinds of industrial fields.