基于干冰低温冷却的大进给铣削TC4钛合金刀具磨损研究

针对TC4钛合金切削加工过程中刀具易磨损、加工效率低等问题,以干冰为冷却媒介对TC4钛合金进行大进给铣削加工,以提高TC4钛合金的切削加工效率,降低刀具磨损。研究了不同冷却方式下的TC4钛合金大进给铣削过程中铣削速度对刀具耐用度的影响规律和干冰低温冷却方式下刀刃形状和刀具材质对刀具耐用度的影响;分析了干冰低温冷却方式下的不同铣刀刀具的磨损特征,明晰了干冰低温冷却大进给铣削TC4钛合金时的刀具磨损机理。研究结果表明,干冰低温冷却可以抑制大进给铣削时的刀具磨损,提高刀具耐用度。此外,圆弧刃三角形刀片比四边形刀片更适合高速大进给铣削。     

TC4钛合金深槽插铣加工

针对钛合金深槽开槽加工效率较低的问题,对TC4钛合金深槽进行插铣开槽试验研究,并对其已加工表面形貌、切屑形态、刀具磨损及切削效率进行了分析。结果表明:插铣加工表面粗糙度较大,铣刀的端面刃为主切削刃,刀具磨损主要发生在铣刀的端面刃。对于钛合金深槽的开槽加工,插铣加工切削过程平稳,具有比层铣更高的切削效率。     

钛合金高速铣刀的开发及试验研究

使用钛合金铣刀在120m/min线速度下进行高速铣削试验,对前、后刀面的磨损进行电镜与能谱分析,发现刀具磨损主要包括磨料磨损、粘接磨损和扩散磨损三种类型。以磨损机理为导向,通过刀具几何结构的设计、刀具基材和涂层的优化,开发了新的钛合金高速铣刀。对钛合金TC4进行高速铣削试验,将开发的钛合金高速铣刀与国外先进的高速铣刀进行对比试验。结果表明:开发的钛合金高速铣刀切削速度可达100-120m/min,并且加工稳定;三向切削力均值和波动幅度均小于国外品牌铣刀,切削更轻快;端铣或侧铣时,刀具磨损均小于国外品牌铣刀,刀具耐用度更高。     

高效加工TC4钛合金的铣削过程数值模拟

目前,难加工材料TC4钛合金在切削过程中存在加工效率低、加工表面质量差和刀具使用寿命低等难题。本文针对提高TC4钛合金的加工效率问题,在高速铣削条件下对立铣刀不同轴向切深侧铣加工TC4钛合金进行仿真研究。利用ABAQUS软件建立三维铣削有限元模型并进行相应仿真试验,获取和分析了不同切削条件下的铣削温度场和铣削力波形,并对比了切屑形态。本研究可为高效铣削TC4钛合金实际加工提供理论依据。     

航空钛合金铣削过程有限元数值模拟

基于材料损伤理论确定了切屑分离准则,建立了钛合金TC4构件铣削过程的有限元模型,利用商业有限元软件(ABAQUS),在给定切削参数条件下,采用不同几何参数(前角、后角、螺旋角)的刀具对钛合金TC4的铣削过程进行了有限元模拟,研究了切削力和切削温度随刀具角度变化的规律,结果表明:铣刀的前角在10°~20°,后角为12°~20°,螺旋角为30°~45°时比较适合钛合金TC4的铣削。     

液氮冷却下大进给铣削TC4钛合金的试验研究

钛合金是现代飞行器的主要结构材料之一,是一种典型的难加工材料。针对切削加工钛合金时刀具磨损快、表面质量不易控制等难题,将TC4钛合金作为研究对象,以液氮作为冷却介质,进行了TC4钛合金的大进给铣削试验,测试了液氮冷却条件下大进给铣削TC4钛合金的铣削力、铣削温度以及刀具磨损等,并与乳化液和低温冷风条件下的测试结果进行了对比分析。结果表明:在以较大的切削速度和每齿进给量铣削TC4钛合金时,采用液氮冷却比使用乳化液能更有效地降低切削力和切削温度;比采用低温冷风冷却能更有效地延长刀具寿命。     

PVD涂层铣刀的制备及其磨损研究

采用物理气相沉积(PVD)对硬质合金立铣刀进行涂层处理,并对钛合金进行铣削测试。研究TiSiN和ZrAlN两种不同类型PVD涂层硬质合金铣刀的磨损情况以及钛合金铣削表面粗糙度和表面形貌。磨损实验结果表明：当主轴转速N、铣削深度a_p、铣削宽度a_e、进给速度v_f分别为8000r/min, 2mm, 0.30mm, 1200mm/min时,无涂层、TiSiN涂层、ZrAlN涂层三种硬质合金铣刀的第一后刀面磨损量分别达到133μm, 61μm, 33μm。钛合金铣削实验结果表明：当铣削参数为主轴转速8000r/min、铣削深度0.1mm、铣削宽度0.05mm和进给速度800 mm/min时,无涂层、TiSiN涂层、ZrAlN涂层三种硬质合金铣刀获得的钛合金铣削表面粗糙度分别为0.35μm, 0.40μm, 0.38μm。ZrAlN涂层可以明显抑制钛合金切削过程中的黏刀现象,降低黏着磨损情况,有效提高硬质合金铣刀的切削性能。     

无污染切削介质下钛合金铣削刀具磨损机理研究

绿色制造和可持续发展的难加工材料的高速切削技术是21世纪重要的发展领域。本文基于绿色制造基础上,针对空气油雾介质和氮气油雾介质下,对钛合金TC4的高速铣削过程中的刀具磨损机理进行了比较系统的试验研究。通过对试验研究结果分析,初步将刀具的磨损归结为粘结磨损、氧化磨损、剥落与崩刃和扩散磨损。     

铣削加工中刀具磨损间接测量的研究

阐述了钛合金(TC4)的切削性能。通过TC4铣削加工时的刀具磨损试验,研究铣削钛合金时硬质合金刀具磨损情况。对TC4工件在不同的时间间隔内进行铣削试验,将每组试验加工后的刀具磨损情况在铝合金板加工形成一系列有刀具磨损信息的孔,利用三坐标测量机测量铝合金板上孔的信息。采用最小二乘方法处理测量的数据,从而得到刀具磨损的相关信息。     

钛合金零件高速铣削刀具磨损的试验研究

高速铣削钛合金时,由于切削区内的切削温度高,加剧了刀具的磨损。通过对钛合金TC4的高速铣削实验,得出带TiA lN涂层的硬质合金刀具切削钛合金TC4时的刀具磨损的变化规律和刀具耐用度公式。通过对刀具磨损特性的分析,研究结果主要是刀具表面层的粘结相Co在高温下丧失对WC颗粒的结合强度,磨损机理以高温下的粘结层撕裂磨损为主。     

Effects of Cutting Parameters on Tool Insert Wear in End Milling of Titanium Alloy Ti6A14V

Titanium alloy is a kind of typical hard-to-cut material due to its low thermal conductivity and high strength at elevated temperatures, this contributes to the fast tool wear in the milling of titanium alloys. The influence of cutting conditions on tool wear has been focused on the turning process, and their influence on tool wear in milling process as well as the influence of tool wear on cutting force coefficients has not been investigated comprehensively. To fully understand the tool wear behavior in milling process with inserts, the influence of cutting parameters on tool wear in the milling of titanium alloys Ti6Al4 V by using indexable cutters is investigated. The tool wear rate and trends under different feed per tooth, cutting speed, axial depth of cut and radial depth of cut are analyzed. The results show that the feed rate per tooth and the radial depth of cut have a large influence on tool wear in milling Ti6Al4 V with coated insert. To reduce tool wear, cutting parameters for coated inserts under experimental cutting conditions are set as: feed rate per tooth less than 0.07 mm, radial depth of cut less than 1.0 mm, and cutting speed sets between 60 and 150 m/min. Investigation on the relationship between tool wear and cutting force coefficients shows that tangential edge constant increases with tool wear and cutter edge chipping can lead to a great variety of tangential cutting force coefficient. The proposed research provides the basic data for evaluating the machinability of milling Ti6Al4 V alloy with coated inserts, and the recommend cutting parameters can be immediately applied in practical production.     

Effects of cutting parameters on tool insert wear in end milling of titanium alloy Ti6Al4V

Titanium alloy is a kind of typical hard-to-cut material due to its low thermal conductivity and high strength at elevated temperatures, this contributes to the fast tool wear in the milling of titanium alloys. The influence of cutting conditions on tool wear has been focused on the turning process, and their influence on tool wear in milling process as well as the influence of tool wear on cutting force coefficients has not been investigated comprehensively. To fully understand the tool wear behavior in milling process with inserts, the influence of cutting parameters on tool wear in the milling of titanium alloys Ti6Al4V by using indexable cutters is investigated. The tool wear rate and trends under different feed per tooth, cutting speed, axial depth of cut and radial depth of cut are analyzed. The results show that the feed rate per tooth and the radial depth of cut have a large influence on tool wear in milling Ti6Al4V with coated insert. To reduce tool wear, cutting parameters for coated inserts under experimental cutting conditions are set as: feed rate per tooth less than 0.07 mm, radial depth of cut less than 1.0 mm, and cutting speed sets between 60 and 150 m/min. Investigation on the relationship between tool wear and cutting force coefficients shows that tangential edge constant increases with tool wear and cutter edge chipping can lead to a great variety of tangential cutting force coefficient. The proposed research provides the basic data for evaluating the machinability of milling Ti6Al4V alloy with coated inserts, and the recommend cutting parameters can be immediately applied in practical production.     

钛合金高速铣削刀具磨损的试验研究

通过高速铣削钛合金TC4的切削试验,讨论了切削参数、刀具材料等对刀具磨损的影响。     

金刚石涂层刀具铣削高硅铝合金的性能研究

选用未涂层、TiAlN涂层及金刚石涂层整体硬质合金两刃平头立铣刀,在相同切削参数下进行高硅铝合金的高速铣削加工试验。试验结果表明:金刚石涂层铣刀具有良好的耐磨性,在切削过程中刀刃磨损均匀缓慢,刀具使用寿命长,加工表面粗糙度值稳定性好,是铣削高硅铝合金的理想刀具。     

铜合金的高速铣削加工的研究

通过对铜合金的高速铣削加工实验,对铜合金的高速铣削加工时的切削力、金属去除率、表面质量、切削热、刀具材料及刀具耐用度进行分析和研究.从而得出,硬质合金和人造金钢石非常适合于对铜合金的高速铣削加工,而且用高速铣削加工出的铜合金零件的表面质量和加工精度是非常理想的,往往毋需再进行进一步的精加工.     

液氮低温切削钛合金实验研究

针对钛合金难加工特点,将液氮作为冷却介质直接喷向切削区进行钛合金TC4低温车削加工,测量其切削力、表面粗糙度和刀具磨损,并与干切削在相同实验条件下对比,分析低温切削对钛合金的影响。实验结果表明:低温切削钛合金,主切削力有所增大,但进给方向力减小,刀具磨损状况与表面质量得到改善,断屑相对容易。     

硬质合金刀具高速车铣和铣削TC4钛合金磨损试验对比

采用H13A未涂层硬质合金刀具对TC4钛合金进行高速正交车铣和铣削试验,并从刀具磨损破损形态、磨损机理及其寿命等方面进行对比分析。研究表明:高速正交车铣和铣削钛合金时,前、后刀面主要以粘结磨损为主,车铣加工时在切削刃口易形成积屑瘤及连续切屑,但对刀具材料粘结较轻;高速铣削时,对刀具材料粘接较重,在前刀面刃口附近形成凹坑及崩刃;后刀面最大磨损的位置不相同。试验对比了相同切削条件时刀具使用寿命,结果表明采用正交车铣加工可以获得更长的刀具使用寿命。     

THE SURFACE INTEGRITY IN MACHINING HARDENED STEEL SKD11 FOR DIE AND MOLD

Milling cutters were evaluated by tool wear, cutting force and vibration. Surface integrity of grinding and milling were investigated by comparing residual stress distributions, metallurgical structure, hardened layer depth and surface roughness. And influence of cutting tool wear on surface integrity was investigated. Experimentations revealed that the preferable surface integrity would be obtained if the proper milling cutter as well as a small wear criterion were adopted to avoid the advent of tempered martensite. The research results pointed out the feasibility of taking milling as the finish machining process instead of grinding in machining hardened steel with high efficiency.     

THE SURFACE INTEGRITY IN MACHINING HARDENED STEEL SKD11 FOR DIE AND MOLD

Milling cutters were evaluated by tool wear, cutting force and vibration. Surface integrity of grinding and milling were investigated by comparing residual stress distributions, metallurgical structure, hardened layer depth and surface roughness. And influence of cutting tool wear on surface integrity was investigated. Experimentations revealed that the preferable surface integrity would be obtained if the proper milling cutter as well as a small wear criterion were adopted to avoid the advent of tempered martensite. The research results pointed out the feasibility of taking milling as the finish machining process instead of grinding in machining hardened steel with high efficiency.