典型钛合金壳体零件加工工艺

随着钛合金的广泛应用,由于其材料强度高,化学活性大,弹性模量较低等原因,其材料的难加工性越来越引起机械加工领域的关注。结合钛合金零件加工领域的技术资料和经验对典型钛合金壳体零件使用加工中心加工的工艺进行了理论探讨,重点介绍了钛合金壳体零件加工中铣削、钻孔、镗孔、攻丝等工艺,在实际运用中可以为钛合金零件加工领域的一线人员提供一定帮助。     

TC11钛合金深孔钻削工艺研究

针对钛合金材料钻削加工的难点,对TC11钛合金薄壁壳体进行了钻削加工方法的探索和研究。从刀具结构、刀片几何角度、切削参数的选择以及对工件的热处理等方面进行改进试验,优选了合理的工艺方案,解决了薄壁壳体内孔钻削加工的技术难题,提高了产品质量。     

低熔点合金灌注在钛合金封装壳体加工中的应用

针对TC4钛合金封装壳体薄壁易变形的结构特点,提出了采用低熔点合金填充至壳体内腔的工艺方法,以提高零件的刚度,解决薄壁壳体机械加工时的变形问题。文中分析了钛合金封装壳体的加工工艺难点及可以采取的工艺措施,探讨了封装壳体加工对腔内灌注填充材料的要求,着重介绍了低熔点合金的材料特性、低熔点合金成分和成分选择.此外对介绍TC4钛合金封装壳体的加工工艺作了简要的介绍。     

解决钛合金薄壁工件切削加工变形的工艺

在机械制造业中,钛合金材料具有其他金属材料无法拥有的特点：比强度高,热强性高,抗蚀性好;合金密度仅为钢的58％,因此利朋钛合金材料做成的薄壁壳体结构件,将成为国防产品通用工件。由于工件壁薄,加工容易变形,径向夹紧力使工件产生弹性变形,刀具磨损快使加工尺寸不稳定,不易保证加工质量,使工件废品率及加工成本居高不下,工件加工变形一直困扰技术人员及加工操作者。     

钛合金的小直径内螺纹攻丝

本文论述在钛合金工件上进行小直径螺纹加工的工艺、刀具设计和切削液选用等。     

钛合金的深孔套料工艺试验研究

根据钛合金的材料特性和切削加工性能,设计和制造了适合于加工钛合金工件的套料钻并制定相应加工工艺,并对钛合金进行深孔套料加工试验.试验结果表明,切削过程稳定可靠,通过套料加工可显著提高钛合金的材料利用率,为钛合金套料提供了一套有效的加工工艺方法.     

液体磁性磨具光整加工TC4钛合金的试验研究

为解决TC4钛合金材料难加工问题,采用液体磁性磨具对TC4钛合金进行了表面加工试验。通过调整工艺参数,采用田口方法对TC4钛合金液体磁性磨具光整加工的工艺参数进行优化。采用单因素试验法,研究磨料类型、磨料粒径、工件转速和电流强度等工艺参数对液体磁性磨具光整加工TC4钛合金材料加工性能的影响,并总结各工艺参数对工件表面粗糙度的影响规律。根据信噪比的望大特性分析得出,在液体磁性磨具光整加工TC4钛合金材料的加工过程中,当使用2 000目的白刚玉,主轴转速为500 r/min,电流强度为1.5 A加工时,工件表面粗糙度相对下降率%ΔRa达到了86.10%。液体磁性磨具光整加工TC4材料表面的最优工艺参数组合为:2 000目的白刚玉,主轴转速为700 r/min,电流强度为2.0 A。同时得出各工艺参数对工件表面粗糙度相对下降率%ΔRa的影响大小依次为:磨料类型磨料粒径工件转速电流强度。当采用2 000目的白刚玉配置的磨料进行加工时,工件的表面粗糙度Ra达到了0.096μm。采用液体磁性磨具光整加工技术可以有效地降低TC4钛合金材料的表面粗糙度和提升其工件表面加工质量,显著改善了传统加工方式中存在的烧蚀和烧伤现象。     

大直径薄壁钛合金壳体加工技术

钛合金材料在航空航天中应用越来越广泛,受结构影响,薄壁钛合金壳体在机械加工中一直是一个比较棘手的问题.文中就一种典型的薄壁钛合金壳体的加工,从方案设计、定位装夹方法等几方面寻求解决途径,提高薄壁零件的加工精度.     

某运载火箭复杂薄壁壳体数控加工工艺研究

针对大型复杂薄壁壳体加工易变形及加工精度难以满足要求的问题，对数控加工工艺进行了研究，以某运载火箭尾段为例，为了能有效控制工件的加工变形，保证成品的加工精度，通过分析工件的结构特征和影响加工变形的主要因素，有针对性地制定了合理的数控加工工艺方案，包括合理安排加工工序、采用适当的去应力时效方法、优化装夹方案和合理规划刀具路径，实现了工件的变形控制和有效装夹，保证了工件的成品精度要求。最后通过实际加工应用，有效验证了工艺方案的正确性和有效性。     

钛合金TC4热轧板切削异常原因分析及改善措施

针对钛合金TC4封装壳体加工异常的现象,从壳体的加工工艺过程、钛合金热轧板材化学成分、金相组织等方面进行了详细分析,判定壳体加工异常的原因在于材料中呈粗大长条状分布的初生仅相,并分析了钛合金热轧板材中产生粗大长条状初生α相的原因。在此基础上,研究了采用固溶处理工艺消除热轧板中粗大初生α相工艺方法。试验结果表明,固溶处理可以改善钛合金TC4热轧板的显微组织,使大部分粗大的初生α相分解为细碎的次生等轴α相,明显改善材料的切削加工性能。     

壳体零件的旋压工艺研究

对某系统中关键零件的加工工艺进行了详细的研究,包括零件的材料、结构、性能、加工工艺,重点研究了零件的旋压工艺特点并分析了旋压工艺参数的选定、旋压设备的选型以及旋压零件质量的保证。     

Assessment of the machinability of Ti-6Al-4V alloy using the wear map approach

The high strength to density ratio of titanium alloys coupled with excellent corrosion resistance even at elevated temperatures make them ideal for aerospace applications. Moreover, the biocompatibility of titanium also enables its widespread use in the biomedical and food processing industries. However, the difficulty in machining titanium and its alloys along with the high cost of its extraction from ore form presents a major economic constraint. In the context of machining economics, the wear map approach is very useful in identifying the most suitable machining parameters over a feedrate–cutting velocity plane. To date, wear maps have only been prepared for the machining of ferrous alloys. In this article, a review of the machinability of Ti-6Al-4V alloy is presented with emphasis on comparing the wear performance of various tool materials. In addition, a new wear map for Ti-6Al-4V alloy is presented based on unified turning tests using H13A grade carbide inserts. This wear map can be used as a guide in the selection of cutting variables that ensure the least tool wear rates. This article contrasts the occurrence of a safety zone in the case of machining steels to that of an avoidance zone for Ti-6Al-4V alloy.     

钛合金复杂构件等温锻造实验研究

钛合金复杂构件通常采用机加工成形,导致成本高、材料利用率低,而且常规的锻造工艺很难满足外形复杂、使用性能要求高的钛合金复杂构件成形过程。提出钛合金复杂构件的新工艺,即先等温锻造成复杂构件形状,然后辅以机械加工的方法成形;通过实验研究,结合力学性能测试和超声波探伤,提出非对称变截面钛合金复杂构件等温锻造成形工艺。实验结果表明,采用该等温锻造成形工艺获得的钛合金复杂构件完全满足系统要求,并可替代机械加工产品;按新工艺加工成形的某钛合金复杂构件,不但降低成本,缩短机加工时间,而且材料利用率也提高到60%以上。     

Machining of Titanium Alloy (Ti-6Al-4V)—Theory to Application

This article correlates laboratory-based understanding in machining of titanium alloys with the industry based outputs and finds possible solutions to improve machining efficiency of titanium alloy Ti-6Al-4V. The machining outputs are explained based on different aspects of chip formation mechanism and practical issues faced by industries during titanium machining. This study also analyzed and linked the methods that effectively improve the machinability of titanium alloys. It is found that the deformation mechanism during machining of titanium alloys is complex and causes basic challenges, such as sawtooth chips, high temperature, high stress on cutting tool, high tool wear and undercut parts. These challenges are correlated and affected by each other. Sawtooth chips cause variation in cutting forces which results in high cyclic stress on cutting tools. On the other hand, low thermal conductivity of titanium alloy causes high temperature. These cause a favorable environment for high tool wear. Thus, improvements in machining titanium alloy depend mainly on overcoming the complexities associated with the inherent properties of this alloy. Vibration analysis kit, high pressure coolant, cryogenic cooling, thermally enhanced machining, hybrid machining and, use of high conductive cutting tool and tool holders improve the machinability of titanium alloy.     

Drilling experiments on a gamma titanium aluminide obtained via electron beam melting

Gamma titanium aluminides are intermetallic structural alloys with many advantages like high temperature and oxidation resistance, low density, high specific strength, rigidity, etc. This makes them promising candidates for critical applications where both mechanical and thermal properties are required. Unfortunately, their machinability is demanding, generating low cutting life and poor surface conditions. A deeper knowledge on the machining parameters is essential for a wider application of these heat-resistant light-weight alloys in aircraft and automotive industry. In this paper, the performance of uncoated carbide drills in drilling a gamma titanium aluminide was analysed. The workpiece material was obtained via electron beam melting (EBM) process, a versatile technology for additive manufacturing of complex metal parts from metal powders. EBM is highly appealing in the field of aeroengine components, and it is particularly interesting in processing gamma titanium aluminides. Cutting performances were measured in terms of tool wear, surface roughness, dimensional and geometric errors. The experimental results show strong dependence of tool wear and part quality on cutting parameters, with poor tool life compared with other work materials.     

钛合金精密零件镗铣加工工艺

对钛合金精密零件加工工艺技术的研究,通过选用适合加工钛合金材料的刀具、切削要素,提高钛合金精密零件加工质量,通过制定合理的热处理参数及工艺流程消除零件加工应力,稳定零件加工尺寸,选用合适的定位方式消除零件的加工过定位,保证零件加工尺寸精度,试验表明此工艺加工方法可消除零件加工变形,稳定加工尺寸,使钛合金精密零件合格率达到95%以上,从而达到保证零件尺寸精度的技术要求。     

ROTARY ULTRASONIC MACHINING OF TITANIUM ALLOY: EFFECTS OF MACHINING VARIABLES

Titanium and its alloys are finding prime applications in industries due to their unique properties. However, the high cost of machining is one of the limiting factors for their widespread use. Tremendous efforts are being made to improve the existing machining processes, and new processes are being developed to reduce the machining cost in order to increase the titanium market. However, there is no report on the systematic study of the effects of machining variables on output parameters in rotary ultrasonic machining of titanium and its alloys. This paper presents an experimental study on rotary ultrasonic machining of a titanium alloy. The cutting force, material removal rate, and surface roughness (when using rotary ultrasonic machining) of a titanium alloy have been investigated using different machining variables.     

高速切削加工钛合金的刀具材料

概括介绍了钛合金的性能特点,分析了钛合金切削加工困难的主要原因,重点对国内外切削加工钛合金的现状作了详细介绍,由此明确了目前国内和国外切削加工钛合金水平的差距,最后指出在国内寻求一种或几种高速切削加工钛合金刀具材料的紧迫性和必要性。     

Problems and solutions in machining of titanium alloys

Titanium alloys are known as difficult-to-machine materials. The problems of machining titanium are many folds which depend on types of titanium alloys. This paper investigates the underlying mechanisms of basic challenges, such as variation of chip thickness, high heat stress, high pressure loads, springback, and residual stress based on the available literature. These are responsible for higher tool wear and worse machined surface integrity. In addition, many cutting tool materials are inapt for machining titanium alloys as those materials are chemically reactive to titanium alloys under machining conditions. To address these problems, latest techniques such as application of high pressure coolant, cryogenic cooling, tap testing, thermally enhanced machining, hybrid machining, and use of high conductive cutting tool and tool holder have also been discussed and correlated. It seems that all the solutions are not yet well accepted in the industrial domain; further advancement in those fields are required to reduce the machining cost of titanium alloys.