本文關鍵詞： 鑄輾復合成形 加工圖 離心鑄造 微觀組織 輾擴參數(shù)　出處：《機械工程學報》2016年04期 　論文類型：期刊論文

【摘要】：環(huán)件鑄輾復合成形工藝具有縮短工藝流程、高效和節(jié)能節(jié)材等優(yōu)點,研究鑄態(tài)環(huán)坯在鑄輾復合成形工藝下的高溫變形行為,揭示其組織演變機理,是實現(xiàn)材料在該成形工藝中成形與成性的關鍵。在不同變形條件下對砂型鑄造和離心鑄造Q235B法蘭坯進行高溫壓縮試驗,分析其流變應力的變化,推導出二者的本構方程。綜合變形溫度和應變速率對材料微觀結構與性能的影響,建立基于動態(tài)材料模型的加工圖。試驗結果表明:二者的流變應力隨著應變速率的增加和變形溫度的降低而增大。離心鑄造法蘭坯的流變應力較低,動態(tài)再結晶易于發(fā)生,且功耗效率值及其變化幅度都要大于砂型鑄造,表明了其顯微組織變化劇烈,演變更加充分。結合二者的熱加工圖及其識別出的典型區(qū)域顯微組織,獲得了適合該法蘭坯輾擴工藝的熱力參數(shù)范圍,離心鑄造可為法蘭坯鑄輾復合成形工藝提供高質量的鑄坯。
[Abstract]:The compound forming process of ring casting and rolling has the advantages of shortening technological process, high efficiency and saving energy, etc. The deformation behavior of as-cast ring billet at high temperature is studied, and the mechanism of microstructure evolution is revealed. It is the key to realize the formability and formability of the material in the forming process. The high temperature compression test of sand mold casting and centrifugal casting Q235B flange billet is carried out under different deformation conditions, and the change of rheological stress is analyzed. The effects of deformation temperature and strain rate on the microstructure and properties of the materials are derived. The experimental results show that the rheological stress increases with the increase of strain rate and the decrease of deformation temperature. The flow stress of centrifugal casting flange billet is low and dynamic recrystallization is easy to occur. The value of power efficiency and its variation range are larger than those of sand casting, which indicates that the microstructure changes sharply and evolves more fully. The range of thermal parameters suitable for the flange billet rolling process was obtained. Centrifugal casting can provide high quality billet for the flange billet casting and rolling compound forming process.
【作者單位】： 太原科技大學材料科學與工程學院;
【基金】：國家自然科學基金重點(51135007);國家自然科學基金(51174140,51205270) 高等學校博士點優(yōu)先發(fā)展計劃(20111415130001)資助項目
【分類號】：TG24;TG306
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本文編號：1530284