Abstract: Aiming at the special conditions of the valves used in coal chemical industry，in order to improve the wear resistance of the valve trim，three typical processing technologies are adopted，which are high velocity oxy-fuel ( HVOF) ，atmospheric plasma spray( APS) and plasma transferred arc( PTA) ; and the typical materials that match the above processing technologies are selected to spray the sample． Abrasion test，hardness test and micro-structure analysis reveal that APS uses much higher spraying temperature than HVOF，which could contribute to the carbide oxidation and dissolution in the matrix，after deposition the coating flexibility increases and the worn surface is difficult to be cracked down and peeled off． In HVOF spraying process，the particles have high impact speed and over-heating does not happen; and the coatings are under compressive stress，have high density and good wear resistance characteristic． The coating of PTA hardfacing has strong binding force with the base material，high hardness and good thickness，its wear resistance characteristic is between those of APS and HVOF．
Key words: coal-chemical industry; control valve; spraying; hardfacing
本站文章未经允许不得转载；如欲转载请注明出处，北京桑尧科技开发有限公司网址：http://en.sunspraying.com/
|
