Analisis Fatigue Failure Suhu Rendah Struktur Batang Duralumin dengan Mesin Siklus Bending

Abstract

Generally non-iron metals use in industries, including aluminum alloy, because of their high strength to weight ratio and favorable (no sparking and high corrosion resistance). Aluminum alloy are often found and used in airplane. Recently, aluminum alloy begins so popular in cryogenic system where it is highly applied at oil industry, low temperature operated, and automotive industry. It is estimated that 50%-90% mechanical failures are due to fatigue failure. This research attempts to predict duralumin fatigue resistance at low temperature and to understand the effect of micro structure on duralumin at low temperature. Several states, which include 15, 30, and 45 in MPa, are given to bending cycle machine. The tested material is duralumin (alloy Al-Cu) which has passed the tests over porosity, fatigue level at low temperature (-19o C) and room temperature (27o C), microstructure, fractography, and macrostructure. Result of research indicates that fatigue resistance increases with lowering work tense at specimen. Average fracture of duralumin fatigue at low temperature is more than 17,8 x 10 cycles, while at room temperature is 13 x 10 5 cycles. During low temperature fatigue test, microstructure shows long and small grains. The deformation during low temperature fatigue test cause smaller grain produce greater slip resistance for specimen.

Keywords: Fatigue Failure, Low Temperature, Duralumin, Bending Cycle