盤類零件工藝編制及鉆孔專用夾具設計（含CAD圖紙）

盤類零件工藝編制及鉆孔專用夾具設計（含CAD圖紙）,零件,工藝,編制,鉆孔,專用,夾具,設計,cad,圖紙 外文資料翻譯譯文 新工具使新機器設計最優(yōu) 當加工鋁時，我們主要關心的是：鋁粘住加工切削邊緣的傾向；保證有好的碎片排屑形成切削邊緣；和保證工具有足夠的中心強度來承受切削力而不被破壞。 技術發(fā)展，比如：Makino MAG系列，已經(jīng)使工具商重新考慮任何工藝水平的機器技術。用正確的加工和編程思路是很重要的。 材料，涂料和幾何形狀是與減小我們所關注問題相關系的工具設計的三個因素。如果這些因素不能一起很好的配合，成功的調整磨削是不可能的。為了成功進行高速鋁加工，理解這三個因素是很必要的。 使組合邊緣最小化 當加工鋁時，一個失敗的切削工具模式是，被加工的材料粘住工具切削邊緣。這種情況會很快削弱工具的切削能力。由粘著的鋁形成的組合邊緣會導致工具變鈍，以至不能切削材料。工具材料選擇和工具涂料選擇是被工具設計者用來減小組合邊緣出現(xiàn)的主要工藝。 亞微米微粒碳化物材料要求很高的鈷濃度來獲得良好的微粒結構和材料強度屬性。隨著溫度的升高，鈷與鋁發(fā)生反應，鈷使鋁與暴露的工具材料碳化物相粘合。一旦鋁開始粘住工具，鋁會在快速的在工具上形成組合邊緣，使工具不可用。 在切削的進程中，減小鋁粘合著的工具的暴露碳化物的秘訣就是找到正確的碳化物的平衡來提供足夠的材料強度。在加工鋁時，為了減小粘附，使用能提供足夠硬度的紋理粗糙的碳化物來獲得平衡，來使變鈍變慢。 工具涂料 當嘗試減小組合邊緣時，第二個應該考慮的工具設計因素是工具涂料。工具涂料的選擇包括：TiN, TiAIN, AITiN，鉻氮化物，鋯氮化物，鉆石和鉆石般的涂料（DLC）。擁有這么多的選擇，航空航天磨削商店需要知道在鋁的高速加工應用中哪一種工作最有效。TiN, TiCN, TiAIN, 和 AITiN工具的PVD涂裝應用進程使這些選項不合適鋁的應用。PVD涂裝進程建立了兩個使鋁粘住工具的模式---表面的粗糙程度和鋁與工具涂料之間的化學反應。PVD進程形成了一個表面，這表面是比底層材料更粗糙的。由這個進程形成的表面“凹凸”使工具中的鋁在凹處快速集結。由于涂料有金屬晶體和鐵晶體特征，PVD涂料是可以和鋁發(fā)生化學反應的。一種TiAIN涂料通常是包含鋁的，這鋁很容易和相同材料的切削表面粘合。表面粗糙度和化學反應特性將會導致工具和工作片體粘在一起，以致形成組合表面。 OSG Tap and Die主導的試驗中，人們發(fā)現(xiàn)在高速加工鋁時，一個沒有涂染過紋理粗糙的碳化物的工具的表面優(yōu)于用TiN, Ticn, TiAIN, 或者ALTiN涂染過的工具。這個試驗不意味著所有工具涂料將減小工具的表現(xiàn)。鉆石和DLC涂料可生成一個非常光滑的化學惰性的表面。在切削鋁材料時，這些涂料很認為是能非常有效的提高工具的壽命。 鉆石涂料被認為是表現(xiàn)最佳的涂料，但這種涂料要一個很可觀的成本。對于表現(xiàn)價值，DLC涂料提供最佳成本，增加大約20%-25%的總工具成本，而壽命相對于未涂染過紋理粗糙的碳化物的工具來是，是增長得很明顯的。 幾何形狀 高速鋁加工工具設計的拇指定律就是使微粒排屑空間最大化。這是因為鋁是一種非常柔軟的材料。Federate通常是可以增長的，它生成更多更大的微粒。 Makino MAG-Series航空航天磨削機器，比如MAG4,要求額外關注工具幾何休和工具強度。擁有強大的80-hp的心軸的 MAG-Series機器將折斷工具如果他們不是用足夠的中心強度設計的。 總的來說，鋒利的切削邊緣一直都可以用來避免鋁的延伸。一個鋒利的切削邊緣將形成高剪切和高表面清潔，形成一個更好的表面和使表面振動最小化。結果是用優(yōu)良的紋理碳化物材料比紋理粗糙的碳化物材料更有可能獲得一個鋒利的切削邊緣。但由于鋁能粘住紋理好的材料，長久保持這各邊緣是不太可能的。 粗略的折衷方案 紋理粗糙的材料是最好的折衷。那是一種很強大的材料，它能擁有一個可觀的切削邊緣。試驗結果表明；在獲得長的工具壽命的同時擁有好的表面的可以的。通過工具來進行油霧冷卻是可以改進切削邊緣的保持的。霧化逐漸使工具冷卻，消除溫度急增的問題。 螺旋角度是一個額外的工具幾何考慮因素。傳統(tǒng)上來說，當加工鋁時，帶有高螺旋角度的工具已經(jīng)被運用。高螺旋角度可以使微粒更快地從部分脫離，但卻增加力和熱，這是由切削運動導致的。一個高螺旋角被用在工具上，并且很大數(shù)量的凹槽可以使微粒排泄。 當以非常高的速度加工鋁時，由增加的力形成的熱量可能會引起微粒與工具焊接在一起。此外，一個有很高螺旋角的切削表面將比低角度的更快產(chǎn)生微粒。僅僅利用兩個凹槽工具設計使低螺旋角和足夠微粒排泄區(qū)域成為可能。由OSG主導的延伸性試驗中，當發(fā)展新工具流水線時，這被證明是最成功的方法。 New tools maximize new machine designs The primary tooling concerns when machining aluminum are: minimizing the tendency of aluminum to stick to the tool cutting edges; ensuring there is good chip evacuation form the cutting edge; and ensuring the core strength of the tools is sufficient to withstand the cutting forces without breaking. Technological developments such as the Makino MAG-Series machines have made tooling vendors rethink the any state-of-the-art machine technology. It is vital to apply the right tooling and programming concepts. Materials coatings and geometry are the three elements in tool design that interrelate to minimize these concerns. If these three elements do not work together, successful high-speed milling is not possible. It is imperative to understand all three of these elements in order to be successful in the high-speed machining of aluminum. Minimize Built-Up Edge When machining aluminum, one of the major failure modes of cutting tools the material being machined adheres to the tool cutting edge. This condition rapidly degrades the cutting ability of the tool. The built-up edge that is generated by the adhering aluminum dulls the tool so it can no longer cut through the material. Tool material selection and tool coating selection are the two primary techniques used by tool designers to reduce occurrence of the built-up edge. The sub-micron grain carbide material requires a high cobalt concentration to achieve the fine grain structure and the material’s strength properties. Cobalt reacts with aluminum at elevated temperatures, which causes the aluminum to chemically bond to the exposed cobalt of the tool material. Once the aluminum starts to adhere to the tool, it quickly forms a built-up edge on the tool rendering it ineffective. The secret is to find the right balance of cobalt to provide adequate material strength, while minimizing the exposed cobalt in the tools for aluminum adherence during the cutting process. This balance is achieved using coarse-grained carbide that provides a tool of sufficient hardness so as to not dull quickly when machining aluminum while minimizing adherence. Tool coatings The second tool design element that must be considered when trying to minimize the built-up edge is the tool coating. Tool coating choices include TiN, TiAIN, AITiN, chrome nitrides, zirconium nitrides, diamond, and diamond-like coatings(DLC). With so many choices, aerospace milling shops need to know which one works best in an aluminum high-speed machining application. The Physical Vapor Deposition (PVD) coating application process on TiN, TiCN, TiAIN, and AITiN tools makes them unsuitable for an aluminum application. The PVD coating process creates two modes for aluminum to bond to the tools――the surface roughness and the chemical reactivity between the aluminum and the tool coating. The PVD process results in surface that is rougher that the substrate material to which it is applied. The surface”peaks and valleys” created by this process causes aluminum to rapidly collect in the valleys on the tool. In addition, the PVD coating is chemically reactive to the aluminum due to its metallic crystal and ionic crystal features. A TiAIN coating actually contains aluminum, which easily bonds with a cutting surface of the same material. The surface roughness and chemical reactivity attributes will cause the tool and work piece to stick together, thus creating the built-up edge. In testing performed by OSG Tap and Die, it was discovered that when machining aluminum at very high speeds, the performance of an uncoated coarse-grained carbide tool was superior to that of one coated with TiN, Ticn, TiAIN, or ALTiN. This testing does not mean that all tool coatings will reduce the tool performance. The diamond and DLC coatings result in a very smooth chemically inert surface. These coatings have been found to significantly improve tool life when cutting aluminum materials. The diamond coatings were found to be the best performing coatings, but there is a considerable cost related to this type of coating. The DLC coatings provide the best cost for performance value, adding about 20%-25%to the total tool cost. But, this coating extends the tool life significantly as compared to an uncoated coarse-grained carbide tool. Geometry The rule of thumb for high-speed aluminum machining tooling designs is to maximize space for chip evacuation. This is because aluminum is a very soft material, and the federate is usually increased which creates more and bigger chips. The Makino MAG-Series aerospace milling machines, such as the MAG4, require an additional consideration for tool geometry-tool strength. The MAG-Series machines with their powerful 80-hp spindles will snap the tools if they are not designed with sufficient core strength. In general, sharp cutting edges should always be used to avoid aluminum elongation. A sharp cutting edge will create high shearing and also high surface clearance, creating a better surface finish and finish and minimizing chatter or surface vibration. The issue is that it is possible to achieve a sharper cutting edge with the fine-grained carbide material than the coarse grained material. But due to aluminum adherence to the fine-grained material, it is not possible to maintain that edge for very long. Coarse compromise The coarse grained material appears to be the best compromise. It is a strong material that can have a reasonable cutting edge. Test results show it is able to achieve a very long tool life with good surface finish. The maintenance of the cutting edge is improved using an oil mist coolant through the tool. Misting gradually cools down the tools, eliminating thermal shock problems. The helix angle is an additional tool geometry consideration. Traditionally when machining aluminum a fool with a high helix angle has been used. A high helix angle lifts the chip away from the part more quickly, but increases the friction and heat generated as result of the cutting action. A high helix angle is typically used on a tool with a higher number of flutes to quickly evacuate the chip from the part. When machining aluminum at very high speeds the heat created by the increased friction may cause the chips to weld to the tool. In addition, a cutting surface with a high helix angle will chip more rapidly that a tool with a low helix angle. A tool design that utilizes only two flutes enables both a low helix angle and sufficient chip evacuation area. This is the approach that has proven to be the most successful in extensive testing performed by OSG when developing the new tooling line, the MAX AL.