The Study of Precision Forging Process for The Rifle Handle

[[abstract]]步槍提把傳統加工製程是NC加工機銑製方式製造，材料規格是選用超高強度的7075鋁合金，本研究是針對步槍提把進行精密鍛造製程的研究與開發，以T91步槍提把為研究載具，期望開發近淨形之精密鍛造製程，並藉由鍛造特性提高產品機械性質，同時縮短加工時間、降低刀具成本，達到生產快速化目的。研究方向以CAE模擬技術結合精密模具設計技術與鋁合金材料特性，達到開發精密步槍提把鍛件，並建立相關製程資料。研究過程首先建立步槍提把之CAD模式，再以DEFORM軟體模擬進行7075鋁合金之鍛造成形過程分析，探討成形性、成形負荷、模具應力、鍛造流線等參數數據，選擇出最佳的成形參數組合，以進行後續提把的鍛造實驗。根據模擬數據，規劃精密鍛造製程，設計鍛造工程與製程參數，進行實驗性實體模具設計與製造，最後執行實體精密鍛件開發，並進行鍛件之尺寸量測與外觀檢察，觀察是否有缺陷發生。根據CAE模擬結果顯示7075鋁合金，在胚料溫度400℃，鍛造噸數424噸時，可完全鍛製7075鋁合金步槍提把鍛件成形，觀察步槍提把鍛件成形過程與模擬結果十分吻合，另實際量測鍛件產品外形結果尺寸公差皆在範圍內，而鍛件硬度量測為HRB82~85間，符合產品規格硬度要求。經計算精密鍛造開發製程加工成本可較傳統NC銑製加工節省成本約60.6%，縮短加工時間53.8%，驗證本次精密鍛造製程開發研究達到效益。[[abstract]]The Rifle Handle processing process is traditional for NC processing machine manufacturing, and material specification is the choice of 7,075 of ultra high strength aluminum alloy. The purpose of this research is discussing the precision forging processing with the handle of T91 rifle. Expecting to built the near net-shape precision forging processing and enhance the strength, toughness and rapid-manufacture with forging property characteristic.This research took Computer Aid Engineering (CAE) simulation method with both the technology of precision mold design and precision forging processing of aluminum alloy, and built the processing technology to develop the precision rifle handle forgings. The first step is setting the CAD (Computer Aid Drawing) model of rifle handle, then analyzing the shape, shaping-load, mold-stress and forging flow line by simulating the forging shaping processing with 7075 aluminum alloy to find the best shaping method to testing the follow-on handle forgings. We design the processing and engineering parameter by analyzing the simulation data then build the mold for this experiment. Finally, we built the handle forging and check if any defective happened with dimension measurement and visual inspection.According to CAE simulation results displayed 7,075 aluminum, in embryo material temperature 400 ℃, forging tons number 424 tons , can full forged System 7,075 aluminum rifle made to forgings forming, observation rifle made to forgings forming process and simulation results is anastomosis, another actual volume measuring forgings products shape results size tolerance are in range within, and forgings hard measure measuring for HRB82~85 between, meet products specifications hardness requirements. Calculate precision forging development process costs can be compared with traditional system of NC milling machining cost savings of about 60.6%, shortening the processing time of 53.8%, verify that the research and development of precision forging process to achieve benefits