nhoshi1

What I am trying to do is to coat the outer surface of track roller (I have components separated) to improve the wear resistance of surface (as for now, top layer gets pretty wore out after few weeks time). So, for that, I contacted few coating companies to check if they can help. And one of them is giving quite an assurance for better results, but their coating process (PVD) involves rise in temperature up to 250 oC (I am trying Tungsten-Carbide-Cobalt coating). I have already tried DLC but that wasn't a success as DLC wore off too. For now, I am interested in testing only. So, my focus is not to loose any hardness, meaning increase is highly desired (coating can give micro-hardness of 1000Hv) and to improve wear resistance. and my question here is same as I asked earlier: my major confusion is even if heating will make the steel components softer, but at the same temperature, coating will be applied which promises increase in value of hardness. So, doesn't it kind of balances it out? Thank you again.

Current hardness is around 60 HRC and coating has the hardness of 72 HRC. I have also found some of the datasheets on the internet, but they are for first time tempering temperature against hardness (after quenching). In my case, objects are already tempered from the producer and I am heating it again. I could not find any data for this scenario.

I have few steel components (tool steel: E52100) and wanted to get them coated in order to improve their hardness and wear resistance. According to my material provider, company first quenches the steel, then performs tempering at the temperature in the range 185-190oC. The coating company has this process in which the temperature will rise up to 250oC, which is higher than tempering temperature. By heating, I know that the surface hardness will reduce but I am not sure about to what extent? After researching for past few days, I have been very confused as some sources says that the tempered martensite does not loose its properties (change back to austenite) until much higher temperature is reached? (Though the articles I found were mostly about carbon-steel, not alloy/tool steel). Plus, my major confusion is even if heating will make the steel components softer, but I will be applying coating at same temperature which promises increase in value of hardness. So, doesn't it kind of balances it out? It would be of great help if anyone can share his knowledge and help me out. Thanks!