绿色切削高强度钢的刀具磨损及切屑形态

分析了微量润滑切削时润滑剂的渗透机理及润滑作用对铣削力的影响。使用传统切削、干式切削及微量润滑三种方式铣削高强度钢(PCrNi3Mo),对比切削性能并探讨微量润滑技术对刀具磨损及切屑形貌的影响。对微量润滑加工过程中切削参数(铣削速度、每齿进给量、铣削深度及润滑剂使用量)对刀具磨损的影响进行研究,利用响应曲面法建立了刀具后刀面磨损模型以确定铣削高强度钢(PCrNi3Mo)时润滑剂的最佳使用量,并利用试验验证。结果表明,微量润滑可有效抑制刀具磨损进程;建立的刀具后刀面磨损模型与试验结果误差较小,具有较高实用价值,微量润滑铣削材料PCrNi3Mo时,润滑剂的最佳使用值约为185mL/h;通过改善切削区的摩擦情况,微量润滑可降低切削区域温度并有效控制切屑形貌。     

低温氮气射流对钛合金高速铣削加工性能的影响

在钛合金的高速切削过程中，切削区温度很高，加速了刀具的磨损，限制了切削速度的进一步提高。为降低切削区温度、防止刀具的氧化磨损，提出在低温氮气射流条件下进行钛合金的高速铣削加工。在干铣削、浇注切削液、常温氮气油雾、低温氮气射流和低温氮气射流结合微量润滑等冷却润滑条件下进行了钛合金的高速铣削对比试验。试验结果表明，低温氮气射流结合微量润滑能够最有效地降低铣削力，抑制刀具磨损。借助扫描电镜的检测手段，研究了不同冷却润滑条件下刀具的失效形式。指出在低温氮气射流条件下高速铣削钛合金时，只要热裂纹的形成与扩展未引起刀具的崩刃及刀面的剥落，进一步降低低温氮气的温度将提高刀具的使用寿命。     

低温最小量润滑高速铣削钛合金的试验研究

基于复合制冷技术研制了一种低温最小量润滑供给装置,在低温最小量润滑(cryogenic minimum quantity lubrication,低温MQL)条件下进行高速铣削钛合金试验,研究了低温MQL对刀具与工件材料的摩擦接触状态、刀具磨损及已加工表面粗糙度的影响。将测量的铣削分力转化为切向铣削力和径向铣削力,以分析高速铣削时刀具与工件材料的摩擦接触状况。研究结果表明:低温MQL可使峰值径向铣削力减小27.6%～34.3%,有效地改善了刀具与工件材料的摩擦接触状态;降低低温MQL的温度有益于微量润滑油润滑功能的发挥并改善刀具与工件材料的摩擦接触状态,可延长刀具寿命,减小已加工表面粗糙度,但效果不明显;低温MQL的良好润滑作用可有效延长高速铣削钛合金时刀具的寿命。     

不同润湿性微/纳织构化刀具切削性能研究

针对15-5PH固溶处理不锈钢等难加工材料切削过程中刀具磨损快速的问题,采用激光加工及表面处理技术制备得到不同润湿性的硬质合金微/纳织构化刀具。通过对15-5PH固溶处理不锈钢的切削试验,研究了不同润湿性微/纳织构化刀具的切削性能及减摩机理。试验结果表明:在微量润滑条件下,刀具表面低润湿性微/纳织构的存在可有效降低切削力、前刀面平均摩擦系数及切削温度,同时还能进一步改善刀—屑界面的润滑状况,减缓刀具磨损。     

15-5PH不锈钢粗加工刀具磨损试验研究

针对15-5PH不锈钢在粗加工过程中刀具磨损剧烈问题,进行涂层可转位刀具铣削15-5PH不锈钢试验,研究了15-5PH不锈钢铣削加工过程中的刀具磨损特性。采用超景深显微镜对刀具的前刀面和后刀面磨损形貌进行了检测,结果表明:在15-5PH不锈钢加工过程中,刀具前刀面主要磨损机理是粘结磨损和扩散磨损,刀具失效形式为片状剥落和崩刃,后刀面则为边界磨损和涂层烧灼,失效形式为崩刃。     

双相不锈钢切削加工工艺

在使用PH13-8Mo高强度不锈钢和以其他不锈钢为主要材质的特种双相不锈钢材料纺机零件进行切削处理的过程中,实际难度较大且道具的磨损程度相对严重,为解决以上问题,文章将双相不锈钢切削加工工艺作为重点研究内容,阐述了相关问题,希望有所帮助。     

切削介质对微细铣刀磨损影响的试验研究

在微细铣削加工中,尚缺乏切削介质对刀具磨损影响的研究.在干切削、浇灌切削液、微量切削液和低温冷风介质下,对6061铝合金进行了微细铣削试验,研究了刀具的磨损形式和机理、不同切削介质对刀具磨损、切削力和表面粗糙度Ra的影响规律.同时,确定出能减小刀具磨损和切削力,提高加工质量的最佳切削介质.结果表明:四种切削介质下刀具磨损的形式不完全相同,粘结磨损与磨粒磨损是造成刀具磨损的主要机理;切削力和表面粗糙度Ra的变化趋势可以辅助判断刀具磨损情况;相比于其它切削介质,微量切削液介质下刀具磨损小,切削力低,工件表面质量好,是微细铣削6061铝合金的最佳切削介质.为深入研究微细铣削刀具磨损和实际加工中选择切削介质有一定的参考价值.     

切削介质对微细铣刀磨损影响的试验研究

在微细铣削加工中,尚缺乏切削介质对刀具磨损影响的研究.在干切削、浇灌切削液、微量切削液和低温冷风介质下,对6061铝合金进行了微细铣削试验,研究了刀具的磨损形式和机理、不同切削介质对刀具磨损、切削力和表面粗糙度Ra的影响规律.同时,确定出能减小刀具磨损和切削力,提高加工质量的最佳切削介质.结果表明:四种切削介质下刀具磨损的形式不完全相同,粘结磨损与磨粒磨损是造成刀具磨损的主要机理;切削力和表面粗糙度Ra的变化趋势可以辅助判断刀具磨损情况;相比于其它切削介质,微量切削液介质下刀具磨损小,切削力低,工件表面质量好,是微细铣削6061铝合金的最佳切削介质.为深入研究微细铣削刀具磨损和实际加工中选择切削介质有一定的参考价值.     

MQCL技术对不锈钢加工刀具磨损的影响研究

本文在低温微量润滑(MQCL)及浇注式冷却条件下对不锈钢展开高速车削实验,对两种冷却条件下的刀具磨损情况进行对比分析。研究表明,两种条件下刀具都发生了磨粒磨损和粘结磨损,但MQCL条件下刀具磨损较轻;MQCL的冷却润滑机理主要为微量润滑油雾在切削区域形成了润滑膜,减小了刀具与工件的摩擦,同时低温冷风的加入对切削区域进行了强力降温。     

高强度钢的切削

高强度不锈钢OCr13Ni6Mo,属于难加工材料,用普通硬质合金刀具粗车铸件毛坯时,前刀面常常“粘刀”,后刀面磨损很快,经常产生崩刃、打刀现象。半精车和精车时,刀具后刀面磨损较快,刀具耐用度低,加工表面粗糙度高。在加工中,经过多次切削试验,终于掌握了它的切削加工性能,保证了加工     

Wear Mechanism of Cemented Carbide Tool in High Speed Milling of Stainless Steel

Adhesion of cutting tool and chip often occurs when machining stainless steels with cemented carbide tools. Wear mechanism of cemented carbide tool in high speed milling of stainless steel 0Cr13Ni4 Mo was studied in this work. Machining tests on high speed milling of 0Cr13Ni4 Mo with a cemented carbide tool are conducted. The cutting force and cutting temperature are measured. The wear pattern is recorded and analyzed by high?speed camera, scanning electron microscope(SEM) and energy dispersive X?ray spectroscopy(EDS). It is found that adhesive wear was the dominant wear pattern causing tool failure. The process and microcosmic mechanism of the tool's adhesive wear are analyzed and discussed based on the experimental results. It is shown that adhesive wear of the tool occurs due to the wear of coating, the a nity of elements Fe and Co, and the grinding of workpiece materials to the tool material. The process of adhesive wear includes both microcosmic elements di usion and macroscopic cyclic process of adhe?sion, tearing and fracture.     

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。     

Cryogenic minimum quantity lubrication machining: from mechanism to application

Cutting fluid plays a cooling–lubrication role in the cutting of metal materials. However, the substantial usage of cutting fluid in traditional flood machining seriously pollutes the environment and threatens the health of workers. Environmental machining technologies, such as dry cutting, minimum quantity lubrication (MQL), and cryogenic cooling technology, have been used as substitute for flood machining. However, the insufficient cooling capacity of MQL with normal-temperature compressed gas and the lack of lubricating performance of cryogenic cooling technology limit their industrial application. The technical bottleneck of mechanical–thermal damage of difficult-to-cut materials in aerospace and other fields can be solved by combining cryogenic medium and MQL. The latest progress of cryogenic minimum quantity lubrication (CMQL) technology is reviewed in this paper, and the key scientific issues in the research achievements of CMQL are clarified. First, the application forms and process characteristics of CMQL devices in turning, milling, and grinding are systematically summarized from traditional settings to innovative design. Second, the cooling–lubrication mechanism of CMQL and its influence mechanism on material hardness, cutting force, tool wear, and workpiece surface quality in cutting are extensively revealed. The effects of CMQL are systematically analyzed based on its mechanism and application form. Results show that the application effect of CMQL is better than that of cryogenic technology or MQL alone. Finally, the prospect, which provides basis and support for engineering application and development of CMQL technology, is introduced considering the limitations of CMQL.     

硬质合金刀具铣削30CrNi3MoV高强度钢的切削性能研究

30CrNi3MoV高强度钢是某兵器型号专用的难加工材料。本文在分析材料铣削特性的基础上,选择了合理的铣刀盘和铣刀片的几何参数,通过刀具磨损与耐用度对比试验优选出了最佳的硬质合金刀具牌号,并给出了铣削过程中硬质合金铣刀片的典型磨破损形态。研究结果表明:添加钽、铌的硬质合金是解决30CrNi3MoV高强度钢铣削工艺理想的刀具材料,在92m/min~186m/min的铣削速度范围内,刀具耐用度可达10min~49min;由于材料切削温度高和机械冲击严重,铣刀片的磨破损形态主要表现为后刀面上狭长的热磨损带,倒棱上长方形的磨损坑,前刀面上扇形剥落和刀尖处三角形崩碎破损等。     

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。     

大进给铣削沉淀硬化不锈钢刀具失效分析及切削参数优化

针对大进给硬质合金刀具铣削沉淀硬化不锈钢（05Cr17Ni4Cu4Nb）寿命短、效率低的问题,采用单因素法和正交试验法开展刀具磨损试验,并进行回归分析,得到了刀具寿命经验公式。利用有限元仿真方法获得了切削力、刀具切削刃温度和应力场分布情况,结合磨损测量结果及磨损形貌分析了刀具的失效机理。根据有限元仿真结果和刀具寿命经验公式,综合考虑切削效率和刀具磨损,运用等寿命-效率曲面响应法进行切削参数优化,得到了刀具的最佳切削参数及在该切削参数下刀具的寿命。     

Experimental study in high speed milling of titanium alloy TC21

In this paper, a number of experiments were carried out to study the machinability of a new damage-tolerant titanium alloy (TC21). Firstly, the effects of milling parameters, tool material, and tool wear on cutting forces were investigated. Secondly, the effects of milling parameters and tool wear on cutting temperature were studied. Finally, the effect of tool material on tool life was explored. Results showed that cutting force, cutting temperature, and tool life were greatly influenced by milling parameters, tool material, and tool wear. Thus, cutting tool matching with proper milling parameters should be carefully chosen to satisfying the tool life in actual production.     

Cutting performance of coated carbide tools in high-speed face milling of AISI H13 hardened steel

In the present study, high-speed face milling of AISI H13 hardened steel was conducted to investigate the cutting performance of coated carbide tools. The characteristics of chip morphology, tool life, tool wear mechanisms, and surface roughness were analyzed and compared for different cutting conditions. It was found that as the cutting speed increased, the chip morphology evolved in different ways under different milling conditions (up, down, and symmetric milling). Individual saw-tooth segments and sphere-like chip formed at the cutting speed of 2,500 m/min. Owing to the relatively low mechanical load, longest tool life can be obtained in up milling when the cutting speed was no more than 1,000 m/min. As the cutting speed increased over 1,500 m/min, highest tool life existed in symmetric milling. When the cutting speed was 500 m/min, owing to the higher mechanical load, the flaked region on the tool rake face in symmetric milling was much larger than that in up and down milling. There was no obvious wear on the tool rake face at the cutting speed of 2,500 m/min due to the short tool-chip contact length. In symmetric milling, the delamination of tool material, which did not occur in up and down milling, was caused by the relatively large cutting force. Abrasion had great effect on the tool flank wear in symmetric milling. With the increment of cutting speed, surface roughness decreased first and then increased rapidly. Lowest surface roughness can be obtained at the cutting speed of about 1,500 m/min.     

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。