Akin Akinci

Study on the wear properties of zinc borate filled polycarbonate composites against 4140 steel under dry friction

ABSTRACT The friction and wear performance of pure polycarbonate (PC) and 2.5, 5, 10, and 30% zinc borate-filled (by wt) PC composites were comparatively evaluated under dry sliding conditions. Wear tests were performed at room temperature under the loads of 5, 10, and 20 N and at the sliding speeds of 0.5, 1.0, and 1.5 m/s. The coefficients of friction of the composites were significantly influenced by an increase in zinc borate content. The friction coefficient of PC was decreased from 0.457 to 0.160 with an increase in zinc borate content, depending on applied loads and sliding speeds. The results showed that the wear rates of pure PC and zinc borate-filled composites decreased with an increase in loads. The wear rates of zinc borate-filled composites were significantly affected from zinc borate content. The wear rate of PC decreased from 9.4 × 10−5 to 6.8 × 10−6 mm3/m with an increase in zinc borate content depending on applied loads.

The Applicability of GRP and NRP Composites in Rehabilitation of Unpressurized Pipes

Glass fiber reinforced polymer (GRP) and needle reinforced polymer (NRP) composites have been used to produce a new kind of thin cross section liner for rehabilitation of in ground sewer pipes. The liner made from resin impregnated glass fiber woven (or plastic needle felt) is in-placed and cured for the rehabilitation of deteriorated pipe. This technique is entitled as cured in place pipe (CIPP) and penetrating to all over the world. Among the renovation technologies, CIPP appears less expensive and more promising than other techniques. CIPP liners are made up of several reinforcement layers impregnated with various thermosetting resins such as epoxy, vinyl ester and unsaturated polyester. Different woven geometries can be used for the felt and tube. In this study, the experimental results obtained from cured composites are given. The mechanical characteristics of CIPP tubes manufactured with different materials were given. Specifically glass fiber and synthetic felt impregnated in thermosetting unsaturated polyester resin were investigated. Standard three point flexural tests were carried out on specimens cut out from the cured liners. Beside these three point flexural tests, abrasive and erosive wear tests were also performed on these samples.