The main thermal spraying techniques

       

Thermal spray techniques are classified according to its heat
source and shape of selected materials. Nowadays, thermal
spraying technology mainly include plasma spraying, arc
spraying, flame spraying and so on.

Plasma spraying

Plasma
spraying is widely used due to it can spray many kinds of materials, process is relatively simple, and good combination of
coating and matrix. The main obstacle to obtain high quality coating of plasma
spraying is that the complicated control of the large number of related
parameters of spraying process. One of the main aspects of the past research is
to improve the performance of thermal spray
equipment, 

The present study is the process of coating formation, including
combination between the coatings, combination of coating and substrate, porosity,
not-melt particle control and so on. The ultimate goal of these studies is that
led to the whole process control and automation of plasma spraying.

Arc
spraying

Arc spray is an economic and reliable
thermal spray technology, generally speaking, spraying
material is limited to metals and alloys, spray on a variety of substrates.  Its applications include
wear-resistant coating, structure anticorrosion coating and wear parts repair,
etc, and it may also be applied to seal field in the future. The current
research focus on how to realize the automatic control of spraying process.

Flame spraying

The
traditional flame spraying is made of combustible gas combustion flame as a
heat source, heating the flame spraying
powder to melt and spray on the substrate surface. High speed oxy-fuel
spraying (HVOF) is one of the main flame spraying technology.