DR T THIRUMALAI,DR R SUBRAMANIAN,DR B RAVISANKAR,DR R DHANASEKARAN
申请号：
IN201741040346
公开号：
IN201741040346A
申请日:
2017.11.13
申请国别(地区):
IN
年份:
2017
代理人:
摘要：
Aluminium matrix composites have been reinforced with Boron carbide (B4C) and Graphite (Gr) for increasing mechanical properties, wear resistance and ultimate tensile strength and reducing the density. Addition of Boron carbide (B4C) improve both strength and wear resistance of composite, but, addition of B4C alone in higher amounts makes the composite brittle and machining difficult. Thus, B4C can be advantageously used as a reinforcement to overcome the problem of strength reduction in Gr reinforced composites, resulting in hybrid composites. Aluminium matrix composites reinforced with up to 12 wt B4C and 3 wt Gr particulates are investigated in the present study. Addition of boron carbide and graphite particles reduces the density of hybrid composites thus resulted in a light weight hybrid composites suitable for automobile applications. Hardness and tensile strength of the hybrid composites increased with an increase in weight fraction of boron carbide. Composite with !2wt.%B4C/3wt% graphite reinforcement showed a significant increase in hardness and correlate well with strength and wear resistance. % Elongation decreased in a linear fashion with increasing reinforcement and AI/9B4C/3Gr hybrid composite showed a reduction in ductility when the B4C content was increased from 0 to 12 wt%. Dry sliding wear and friction behavior of unreinforced alloy and hybrid composites showed that the wear rate increased with increasing load and the highest wear was observed at 30 N for all the three sliding speeds (1 to 3 m/s). Maximum wear rate was observed in unreinforced Al alloy (Al) and the lowest in AI/9%B4C/3%Gr composites which can be attributed to the significant improvement in resistance due to presence of B4C and graphite particles. Increasing percent B4C reinforcement promotes stronger material transfer from the counter face. Oxidation due to high interfacial temperature resulted in the formation of a protective Mechanically Mixed Layer (MML). Wear res
