【摘要】：隨著制造技術自動化的發(fā)展趨勢,汽輪機葉片毛坯的成形質量直接影響汽輪機葉片質量以及能量轉換效率。國內的葉片毛坯成形技術主要依靠人工自由鍛造及擠壓鐓頭成形,成形質量具有較大的隨機性,生產加工效率無法滿足現(xiàn)在的企業(yè)需求,同時葉片毛坯的設計過程需耗費大量的人力與時間,增加了葉片生產周期及企業(yè)制造成本,所以亟需更加先進的設計技術和制造成形工藝運用到葉片毛坯的生產過程中。為此,本文著力于探究先進的葉片毛坯徑向鍛造成形工藝,開發(fā)出適用于葉片毛坯徑鍛成形的輔助工藝系統(tǒng),提高葉片毛坯的成形質量以及生產效率,實現(xiàn)葉片毛坯從設計到鍛造成形過程的規(guī)范化、自動化及系統(tǒng)化,基于此本文主要進行的研究工作如下:(1)以葉片常用材料0Cr17Ni4Cu4Nb不銹鋼為研究對象,對其在900~1200℃,應變速率在0.001s-1~10s-1范圍內的熱變形流變行為進行研究分析,基于Prasad塑性失穩(wěn)判據(jù)以及動態(tài)材料模型(DMM),繪制0Cr17Ni4Cu4Nb不銹鋼的熱變形能量耗散圖和熱加工圖,揭示0Cr17Ni4Cu4Nb不銹鋼在熱變形條件下組織演變規(guī)律以及熱變形機理,通過對熱加工圖的分析,獲得失穩(wěn)變形參數(shù)范圍及最佳熱變形參數(shù)范圍,為0Cr17Ni4Cu4Nb不銹鋼熱加工工藝制定和優(yōu)化提供理論依據(jù)。(2)基于熱加工圖分析得到的最佳熱變形參數(shù),借助Simufact.Forming鍛造分析軟件,建立汽輪機葉片毛坯四錘頭徑向鍛造仿真模型,側重分析了在工藝參數(shù)、錘頭類型及結構參數(shù)不同情況下,葉片毛坯鍛后的鍛透性、尺寸精度、內部晶粒尺寸分布以及外觀缺陷情況,借助數(shù)學評價手段處理仿真數(shù)據(jù),通過比較分析不同鍛造條件下的仿真結果,得到不同鍛造工況下最佳的鍛造工藝參數(shù)、錘頭類型以及結構參數(shù),給設計人員在錘頭結構參數(shù)設計及選型和工藝參數(shù)確定方面提供參考。(3)通過對葉片毛坯設計技術的歸納總結,結合實際經驗,構建了葉片毛坯自動化設計體系框架,將由葉片成品鍛件到葉片毛坯設計及原始坯料確定的逆向設計過程以數(shù)學模型創(chuàng)建聯(lián)系。同時,對徑鍛錘頭進行分類,依據(jù)徑鍛錘頭的設計準則及結構特點,將其設計過程做參數(shù)化處理。此外,根據(jù)徑向鍛機鍛造過程的運動特性,以典型圓柱臺階式毛坯為例,對其徑鍛工藝成形過程進行了探究分析。(4)以葉片毛坯和徑鍛錘頭設計及徑鍛成形工藝控制數(shù)學模型為基礎,結合C#與UG/NXOpen二次開發(fā)技術,開發(fā)出基于參數(shù)驅動的葉片毛坯徑向鍛造工藝輔助系統(tǒng),實現(xiàn)葉片毛坯及徑鍛錘頭設計過程的參數(shù)化自動化,縮短葉片毛坯設計周期,提高毛坯的生產效率。同時,根據(jù)毛坯鍛造工步圖生成的工藝控制參數(shù)表,給徑鍛上位機控制軟件編程提供方便。
[Abstract]:With the development of manufacturing automation, the forming quality of turbine blade blank has a direct impact on turbine blade quality and energy conversion efficiency. Domestic blank forming technology mainly depends on artificial free forging and extrusion upsetting. The forming quality is random, and the production efficiency can not meet the needs of enterprises. At the same time, the design process of blade blank needs a lot of manpower and time, which increases the production cycle of blade and manufacturing cost of enterprises, so it is urgent to apply more advanced design technology and manufacturing forming technology to the production process of blade blank. Therefore, this paper focuses on exploring the advanced radial forging forming technology of blade blank, developing an auxiliary process system suitable for blade blank radial forging forming, and improving the forming quality and production efficiency of blade blank. In order to realize the standardization, automation and systematization of blade blank from design to forging forming process, the main research work based on this paper is as follows: (1) taking 0Cr17Ni4Cu4Nb stainless steel, a common material of blade, as the research object, it is studied at 900 鈩，

本文編號：2313069