I performed dry sliding reciprocating wear test on nickel based thermal spray coatings. Generally, wear rate and COF decreases as we increase the temperature. During my experiment, COF decreased while wear rate increased to a large extent at high temperature. In few papers, I got to know that after reaching certain temperature, wear rate trend changes. Please provide some insights. Connectivity with related research works would be much appreciated.
In a friction couple, the hardness of components is one of the most important influencing factors. The increase in temperature can decrease the hardness of one or both of the contacting surfaces, which can cause increased wear. In addition, when the temperature increases, the wear mechanism can change from abrasive to adhesive wear, which can lead to a sudden increase in wear. Another factor affecting wear and friction is surface oxidation. The higher the temperature, the more the contacting metallic surfaces oxidize and the thicker the oxide layers. Depending on the alloy composition, oxidation can have different effects on friction.
Vadim Verlotski Sir, Can you provide some referral research papers for your answer? Because in few papers, I found The hardness decreased as the temperature increased but at the same time, the COF and wear rate both decreased. And in the same paper, they provided adhesive wear to be one of the prominent reason for decrease in wear rate at High Temperature.
It depends on difference between the rate of oxidation and rate of material removal. If the rate of material removal is higher, wear rate will increase with increase in temperature and vice versa. However COF will be low in both the cases.
Neelima Khare Ma'am, can you please provide a relevant reference paper.