Serious Education ... plus the most fun you can have in metal finishing.
Maximum Hardness of Hard Chromium plating(1999)
I would like to know the maximum possible hardness achievable from a hard chromium plated deposit of approximately 200 microns thick?What should be the temperature,current density,chemical composition,concentration etc?any particular type of catalyst?SHAUNAK SHAH
- - MUMBAI,INDIA
I checked properties of electrodeposited metals and alloys by Safranek. There are references cited that go as high as 1500 kg/mm2. I have no idea what this would equate to in Birnell or Knoop or Vickers which are the standard references for microhardness. Please note that hardness is not a linear relationship with wear resistance. Being able to achieve an unusually high hardness has to be proven to be worth the unusuall effort and it has to be proven commercially feasable. It must also take into account what it does to the hydrogen embrittlement and how high has the internal stress gone to. Then, will it plate to the metal of choice, and will it stay on. If you are looking for wear resistance, you might also look at some of the high energy plasma deposits. Just plain old well applied chrome works for a great many applications and is hard enough to do a great job on, let alone some of the exotic things. Boron electroless nickel is another coating that you would do well to investigate. Finally, the optimum choice of a coating depends on what the application will be, not the hardness. Sorry if this sounds a bit "snippy", but You probably have not asked the correct question, and my normal response is "it depends".James Watts
- Navarre, Florida
PLEASE, I NEED INFORMATION ABOUTF HARD CHOMIUM PLATING WE ARE WORKING IN BRUSH PLATING PROCESSES BUT WE NEED TO EXPAND OUR BUSINESS TO MORE INDUSTRIAL PROCESSES. WE WORK WITH PETROLEUM, NAVY, AVIATION AND GENERAL INDUSTRIAL COMPANIES. SEND YOUR INFORMATION AS SOON AS POSSIBLE. SINCERELY, CESAR MEJIACESAR MEJIA
- Quito, Ecuador