Prediction of the phase constitution of the multi-principle elements alloys (MPEAs) with various element numbers is important for alloy design and performance optimization. Herein, valence electron density parameter, $\alpha$, is proposed as an improvement of the valence electron concentration by including the impact of atom volumes. The phase constitution of numerous MPEAs is well predicted by the priori α-${\mathrm{\Delta }H}_{\mathit{mix}}$(enthalpy of mixing) criterion, evidenced by the distinguishing of FCC single phase, FCC and BCC dual-phase and BCC single phase. The similarity of elements in MPEAs is evaluated by the derivative of α and ${\mathrm{\Delta }H}_{\mathit{mix}}$with respect to atomic percentage, which successfully predicts the phase constitution of CrFeNi with addition of Ti, Zr, Al, Cr, Fe, Ni, Co and Cu. This work provides valuable insights into priori judgement of the phase constitution of MPEAs in the view of the relationship between elements.

预测具有各种元素数量的多主元素合金 (MPEA) 的相构成对于合金设计和性能优化很重要。这里，价电子密度参数，$\alpha$, 被提议作为通过包括原子体积的影响来改进价电子浓度。大量 MPEA 的相构成可以通过先验α很好地预测-${\mathrm{\Delta }H}_{\mathit{混合}}$（混合焓）标准，通过区分 FCC 单相、FCC 和 BCC 双相和 BCC 单相来证明。MPEA 中元素的相似性通过α和${\mathrm{\Delta }H}_{\mathit{混合}}$关于原子百分比，它成功地预测了添加 Ti、Zr、Al、Cr、Fe、Ni、Co 和 Cu 的 CrFeNi 的相组成。这项工作为从元素之间的关系角度对 MPEA 的相位构成的先验判断提供了宝贵的见解。