Micro/nano-mechanical behaviors of individual FCC, BCC and FCC/BCC interphase in a high-entropy alloy

•Micro-pillar compression tests were carried on a multiple high-entropy alloy.•Deformation behaviors of FCC, BCC and their interphase pillars were analyzed.•The strain bursts weakened with increasing strain in interphase pillar.•Interphase pillar exhibited better mechanical properties compared with FCC and BCC.•Revealed the relation between small scale deformation and interphase strengthening.