高熵合金因其具有良好的力學性能和應用價值成為當今研究的熱門題目。高熵合金的成分設計以及各個元素之間的相互作用，一直是高熵合金研究領域的核心問題。因此，研究個元素對高熵合金組織及性能的影響，無論從基礎研究的角度考量還是從應用研究的角度考量，都具有實際上的意義。 先前研究的Al50Ti20Cr10Mn15V5 高熵合金為同時具有體心立方以及面心立方的雙相結構，本文取該合金為基體，分別向其中添加硼元素以及鉭元素，以透過固溶強化來提高合金的強度。本文採用電弧熔煉製作試片，進行XRD分析、掃描式電子顯微鏡(SEM)、EDS分析以及壓縮力學性能測試。透過對(Al50Ti20Cr10Mn15V5)100-xBx、Al50Ti20Cr10Mn15V5 + x vol.% Ta兩組合金系的相組成，顯微組織，成分分布及力學性能進行分析，系統的研究其力學性能與組織結構之間的關係。根據實驗結果分析，隨著硼元素的含量增加(原子比為0%-0.5%)，合金的硬度，隨著合金元素含量的增加，維氏硬度從316Hv逐漸增加至363Hv，合金的壓縮降伏強度呈現先增加後減少的趨勢，最大增幅為硼元素添加量為0.1 at.%時從705 MPa增加至1004 MPa。隨著鉭元素含量的增加(體積百分比為0%-10%)，隨著元素含量的增加合金的壓縮降伏強度增加至1605 MPa，合金的維氏硬度增加至540Hv。 其中在兩個系統中，機械性質最好的成分為(Al50Ti20Cr10Mn15V5)99.9B0.1，其壓縮降伏強度為1002 MPa，最大抗壓強度到達1991 MPa，壓縮率則是37%，根據微結構的觀察，發覺相比例與機械性質會有關聯，增加Al8Mn5相的比例，都可預期會有不錯的機械性質。 ;High entropy alloys have become a hot issue of latest research due to their good mechanical properties and application value. The component design of high entropy alloys and the interaction among the elements have been the critical factor. Therefore, it is important to figure out the effect of each element on the microstructure and mechanical properties of high entropy alloys. The previously study found out Al50Ti20Cr10Mn15V5 medium -entropy alloy obtain a dual-phase structure of body-centered cubic and face-centered cubic. In this research, B or Ta elements are added to it to improve the strength of the alloy through solid solution strengthening. All ingots of (Al50Ti20Cr10Mn15V5)100-xBx (x=0-0.5%) and Al50Ti20Cr10Mn15V5 + y vol.% Ta (y=0-10) were prepared by arc melting. According to the analysis results, as the content of B element increases, the hardness increases from 316Hv to 363Hv. The optima compressive yield strength occurs at B=0.1 at.% which is 1004 MPa and 705 MPa for base alloy. With the increase of Ta element content the hardness of the alloy increases from 316Hv to 540Hv. The optima compressive yield strength occurs at Ta=10 vol.% which is 1605 MPa Among two systems, (Al50Ti20Cr10Mn15V5)99.9B0.1 obtain compressive yield strength 1002 MPa, the ultimate compressive strength 1991 MPa, and the compressibility 37% consider as the most promising composition. According to the microstructure observation results, the ratio of two phase related to the mechanical properties, increasing the proportion of the Al8Mn5 phase can be expected to have better mechanical properties.
