Investigating effects of element composition on the microstructure and mechanical properties of three types FeCrAl alloys through small punch test

Abstract

This study investigated the effects of element composition on the microstructure and mechanical properties of three FeCrAl alloys (denoted as Q1, Q2, Q3). The addition of reactive elements (REs) 2 wt% Mo resulted in a 60 % refinement of grain size and an increase in kernel angle misorientation (KAM). Alloy texture was notably influenced by elemental composition, and γ texture (111)[01¯1] exhibited higher energy than (111)[12¯1]. The {110} 〈111〉 slip system exhibited greater resistance to deformation and lower susceptibility to activation than {123} 〈111〉. The yield load (Py-CEN), maximum load (Fm), and fracture energy (Esp) of the alloys at 298 K, 573 K, 723 K, 873 K, and 1023 K were evaluated through small punch test (SPT). The Fm of the three alloys were two-staged with notable temperature dependence. In this context, Q1 exhibited the lowest absolute slope of 2.97 (Q2: 3.44, Q3: 3.46) in the second stage. Furthermore, the Esp value of Q3 was the lowest at room temperature (RT, 298 K) and the highest at high temperatures (873 K and 1023 K) among the three alloys. The obtained results of SPT at different temperatures suggested a strong temperature dependence in the mechanical properties.

Keywords

• FeCrAl alloys
• Microstructure
• Texture
• Small punch test
• High temperature