本團隊研究輕量化合金錳鋁鋼的相組成與對應的相變化數十載，具有多項發表成果，且本研究團隊嘗試在四元錳鋁鋼的基礎下添加鎳，使其成為五元的鎳錳鋁鋼，探討鎳添加的效應。本論文研究成分為Fe-20 Ni-15 Mn-3.0 Al-0.6 C (wt.%)的五元鎳錳鋁鋼，探討此五元合金鋼經1100℃固溶處理的組成相、經後續低溫恆溫處理的組成相與對應的相變化關係。本合金鋼經固溶處理後為單一沃斯田體相；固溶處理後在600℃至950℃的溫度區間，於沃斯田體基地內生成富鎳鋁的BCC (α)析出物；在600℃至800℃的溫度區間，於晶界處析出M23C6碳化物，並發現在其周圍伴隨著BCC晶粒析出，如此M23C6碳化物與周圍的BCC晶粒形成特殊的層狀組織。在室溫下，此富鎳鋁BCC析出物晶粒是由(BCC + B2)奈米晶粒所組成，其原因為富鎳鋁相析出物於600℃以上高溫時為BCC相，在淬水的急速降溫過程中經由spinodal相分離分解成含富鎳鋁的BCC相奈米晶粒基地與含低鎳鋁的BCC相奈米晶粒，其中含富鎳鋁相奈米晶粒基地於冷卻過程，再經由有序相變化轉變為B2相。於600℃以上高溫時的BCC析出物於冷卻過程的連續反應式如下：α → α' + α'' → α' + B2。

The team has studied the phase composition and corresponding phase changes of lightweight alloyed manganese-aluminum steel for decades and has published many results. The research team also tried to add a nickel to the quaternary manganese-aluminum steel to make it a five-element nickel-Manganese-aluminum steel, to investigate the effect of nickel addition. This paper studies the five-element nickel-manganese-aluminum steel whose composition is Fe-20 Ni-15 Mn-3.0 Al-0.6 C (wt.%), discusses the composition phase of this five-element alloy steel after solution treatment at 1100℃, and the subsequent low-temperature relationship between the composition phase of constant temperature treatment and the corresponding phase change. The alloy steel is a single austenite phase after solution treatment; after solution treatment, BCC (α) precipitates rich in nickel and aluminum are formed in the austenite base at a temperature range of 600 ° C to 950 ° C; In the temperature range of 600°C to 800°C, M23C6 carbide precipitates at the grain boundary, and it is found that BCC grains precipitate around it so that M23C6 carbide and the surrounding BCC grains form a special layered structure. At room temperature, the nickel-rich aluminum BCC precipitate grains are composed of (BCC+B2) nano-size particles, the reason is that the rich-nickel-aluminum phase are BCC phases at high temperatures above 600 ° C during the rapid cooling process, the spinodal decomposes separation in the BCC phase nano-size particles base containing nickel and aluminum and the BCC phase nano-size particles containing low nickel and aluminum, and the nanocrystal grain containing nickel and aluminum phase is based on the cooling process, and then transformed into the B2 phase through an ordering phase change. The continuous reaction formula of BCC precipitates in the cooling process at a high temperature above 600°C is as follows: α → α' + α'' → α' + B2.

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