The Effects of Austempering Temperature and Time on Mechanical Properties of Ductile Cast Iron Grade FCD450

Abstract:

The purpose of the study was to inspect microstructure, mechanical properties and impact toughness of ductile cast iron grade FCD450 produced by austempering process. The study focused on austempering parameter, which effected impact toughness of material at low temperature. The FCD450 was initially temperature austenized at 885°C (1625˚F) for 2 hours. Austempering was carried out at three different temperatures of 271°C (520˚F), 313°C (560˚F) and 357°C (675˚F). The austempering temperature were varied at 1.5, 2.5 and 3.5 hours. X-ray diffraction was showed that the austempered ductile cast iron (ADI) microstructure consists of austenite and ferrite. The results showed that when austempered at 357°C (675˚F) for 2.5 hours has highest hardness and impact energy at low temperature. The dimple ductile fracture of ADI fracture surfaces was revealed by scanning electron microscope (SEM).

• Periodical: Key Engineering Materials (Volume 856)
• Pages: 92-98
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.856.92
• Online since: August 2020
• Authors: Janthira Chantarach*, Rungsinee Canyook
• Keywords: Austempering, Ductile Cast Iron, Impact Toughness, Mechanical Properties

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