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A D V A N C E D M A T E R I A L S & P R O C E S S E S | J A N U A R Y 2 0 2 0 2 9 As forged incoming material displaying cracks and alpha case, requiring conditioning. The same material fully conditioned by the MetCon process, ready for forging or rolling. Crack tips have been removed and more parent material is preserved than by traditional condition- ing methods. there were implications that went far beyond creating a uniform surface for medical components. What he saw was the opportunity to change one of the most time-consuming, wasteful and hazardous steps in the processing of ti- tanium from ingot to mill products—the conditioning process. Processing titanium from ingot to finished mill product form and size re- quires multiple steps in which themate- rial is heated, reshaped by mill forging, mill rolling, or extrusion, then allowed to cool. Conditioning must be done af- ter each step to remove the brittle, ce- ramic-like oxygen enriched phase of titanium called alpha case that covers the surface at high temperatures and the cracks that can extend into the ma- terial to a depth of 5% or more with cooling. Traditional subtractive condi- tioning methods—grinding, machining and acid pickling—remove 3 to 7 vol% that only a small number of concentrat- ed mineral or inorganic acids will have any effect on the metal. These acids, and hydrofluoric (HF) acid in particular, are among the most dangerous known. The acceptance of historical scholarly knowledge and the nature of these ac- ids suggest limited incentive to explore alternative chemical means to treat titanium. Electropolishing of titanium has long been a standard technique em- ployed in labs to prepare titanium samples for metallographic study and analysis. However, the recognized tita- nium electrolytes used are even more dangerous than the HF pickling acid. Metallurgy students are taught as a matter of course to electrolytically mi- cropolish their titanium samples using these acids. They also learn stringent safety procedures and how to employ the elaborate safety equipment that is mandatory with their use. The procedures Clasquin began experimenting with were suggested by his knowledge of anodizing titanium and passivating stainless steel. These techniques employ weak acids and a range of electrical currents and voltag- es in open air without requiring hazard- ous material precautions. Eventually, after extensive experimentation, he no- ticed the titanium components he was treating were taking on a brighter, shini- er, and more similar appearance, which encouraged him to conduct further tri- als and also to study the titanium litera- ture. However, he could find nomention of similar processes yielding similar re- sults. He also found no mention of any effective processes that were as safe and green as what he was doing. At this point, Clasquin decided it was time to find some backers, ideally people with a working knowledge of the titanium business who might be interested in funding further development efforts. IMPROVED CONDITIONING The search led him to Kurt Faller, a titanium industry consultant with met- allurgical training and in-depth corpo- rate experience in the titanium industry. In time, as Faller became more familiar with Clasquin’s techniques, he realized of the piece being processed as waste during each step. Faller knew it is the significant con- ditioning losses that largely drive the high cost of titanium, and anything that can improve yield is highly valuable. Based on preliminary analysis, he saw the potential to substantially increase the yield of each conditioning step, giv- ing producers much more material to sell at virtually no extra cost. The po- tential cumulative yield improvement suggested a step change in the cost of making titanium. However, there were concerns: Would the process work as effectively on large metal forms? Was it scalable? Were the economics really as good as they seemed? MetCon LLC, the company that Faller and Clasquin formed, answered these questions. In comparison to tra- ditional methods the MetCon pro- cess removes much less material—just