Chemical Vapour Deposition & Infiltration (CVD & CVI)

PSI Ltd is a specialist designer and manufacturer for R&D laboratory-scale systems to Production plant for the processing of novel materials. The company has previously designed and installed CVD/CVI equipment for the production of ceramic matrix composites for special applications e.g.satellite technology.

Typical CVD/CVI Coatings:-

Coating Material	Process Gases	Typical Deposition Temperatures (degC)
Silicon Carbide	CH3SiCl3	1300
Boron Nitride	BCl3-NH3	1800
Carbon (graphite)	CH4-H2	2200
Titanium Carbide	TiCl4-H2	800
Titanium Nitride	TiCl4-N2	900
Silicon Nitride	SiCl4-N2-NH3	1300
Aluminium Nitride	AlCl3-NH3	800

The PSI CVD/CVI systems are designed and tested to international standards. Constructed from stainless steel the vacuum-pressure vessel encases either a vertically or horizontally orientated corrosion-resistant furnace. Typically manufactured in graphite the retort facilitates hot zones of 600mm diameter x 900mm long down to research-scale systems of 150mm diameter x 460mm. Furnace temperatures of 1300degC are achieved as standard with a high temperature alternative to 2200degC. Specialist, chemically-resistant vacuum facilities are essential as the gas scrubbing system for compliance with local disposal regulations.
With some CVI processing taking days to complete, a fully-automated PLC-based control system and data-logging is essential. Computer-control is available for remote operation and full process data-logging for QC/QA requirements. For client satisfaction purposes, it is PSI’s policy to define the eventual equipment specification only after technical discussion with the client and our own consultants.