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Commercial acceptance of laser coating technology suffered for many years due to questions about its economic viability. During this period, however, many companies, universities, and government research groups were busy developing the technology to overcome these questions. Today, laser coating technology is having a major impact as a high quality, economical method of hardfacing for wear and corrosion resistance in several key industries. This has occurred because of advances in five key areas:
1. High power laser design
2. Method of alloy deposition, and associated hardware
3. In-process feed back control system hardware/software development 4. Alloy systems
5. Marketing/sales sophistication
High power lasers have improved in mode stability, power conversion efficiency, and optical flexibility (reflective vs. transmissive materials). This has enabled the process engineer to increase deposition efficiency, and maintain flexibility on the use of optics specifically designed for a user application. Improvements in the method of alloy deposition have led to developments such as the DPF system with specialized nozzles developed for specific user applications. Another effective technique includes the use of pre-fabricated cast alloy chips that are welded to the component surface on the specific area requiring protection. The development of feedback control systems that integrate process control software with hard tooling, the laser, and the alloy delivery system are greatly improving process reliability and product quality. Because of this, "in-process" quality control is becoming a viable alternative to traditional methods of quality control. Metallurgical evaluations of some of the most widely used hardfacing alloys and base materials have been investigated by numerous researchers. Analysis has confirmed that laser applied coatings are of high metallurgical quality, extremely low in dilution, and distort less due to low heat input. The technology can also be used to apply. wear/corrosion resistant alloys heretofore considered unweldable. These technological advances, coupled with application experience have proven that laser coating technology is not only a viable alternative to conventional hardface and/or spray coatings; but in many cases significantly reduces the overall manufacturing costs of a coated product. Early marketing efforts focused on direct "coating process to coating process" comparisons with competing technologies.
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