Investigation of the friction and wear behaviors of polyoxymethylene/linear low-density polyethylene/ethylene-acrylic-acid blends

The friction and wear behavior of polyoxymethylene/linear low-density polyethylene/ethylene-acrylic acid (POM/LLDPE/EAA) blends is explored using an MM-200 wear tester. The results show that the friction and wear properties of POM were greatly improved after an amount of LLDPE and EAA was added. The friction coefficient and wear scar width of POM are much higher than those of POM/LLDPE/EAA blends under the same condition. The SEM analyses show that POM and POM/LLDPE/EAA blends exhibit totally different wear mechanisms. The wear mechanism of POM is dominated by adhesive. The transfer film of POM is formed on the surface of the steel counterpart. For POM/LLDPE/EAA blend, the lamellar debris is found on the steel ring surface sliding against POM/LLDPE/EAA blend, which helps to decrease the friction coefficient and wear scar width. The lubricate layer formed in the contact surface prevents the bulk from serious wear. Therefore the friction coefficient of POM/LLDPE/EAA blend thus reduced remarkably and anti-wear property got greatly improved.