英语翻译In ultrasonic machining,metal removal is effected with t

英语翻译
In ultrasonic machining,metal removal is effected with the help of abrasive grains which are made to impinge repeatedly upon the workpiece surface by a tool oscillating at a high frequency.The tool cross-section is of a shape similar to that of the desired hole-only it is a little smaller in size in order to compensate for the overcut during the process.The tool oscillates at frequencies of the order of 15 KHz to 30 KHz with an amplitude ranging from 0.1 mm to 0.3 mm.the abrasive grains are carried to the gap between the tool and the workpiece with the help of a carrier fluid,generally water.The circulation of slurry also takes away the worn-out grains and the machining debris,and replaces them by workpiece; the tool also gets reduced in size due to the cutting action of the abrasive grits.Thus the drilled hole by ultrasonic machining is tapped,i.e.larger at the top.By compensating the tool wear properly,close tolerances can be obtained.
Fig.18-4 shows the schematic diagram of the USM equipment.It consists of an oscillator that converts the 50 Hz power supply into high frequency (15 KHz to 30 KHz) power which in turn is converted into mechanical oscillation with the help of a magnetostrictive or piezo-electric transducer.Of the two types,the piezo-electric transducers are more efficient,i.e.they involve less lose of power,and hence do not require cooling.The magnetostrictive transducers generally found in old machines are less efficient due to high eddy current losses and hence may require cooling.
The power rating of modern machines varies from 0.06 to 4 kw.Some of the designs have rating even up to 20 kw.
Applications
The process has been successfully employed for following applications.
(1) For machining of hard and brittle materials that cannot be machined by conventional means.Difficult to machine materials include glass,diamond and tungsten carbide,etc.wire drawing dies of diamond and tungsten carbide are drilled by using the USM process.
(2) For machining of circular and non-circular holes with straight or curved axes.
(3) Threading of hard materials.This can be done by having appropriate tool and workpiece motions.
(4)It has also been successfully used for machining of geranium,silicon,ceramics,carbon plates,quartz,tool steel,synthetic ruby,etc.
(5) For drilling of non-circular holes in hard metals.
Limitations
The major limitations of the process are as follows:
(1) Low machining rates are achievable as compared to the conventional machining processes.
(2) It is difficult to machine very deep holes,as the slurry movement is restricted.
(3) It is difficult to design the correct size of the tool to get exact dimensions on the job.
(4) There is high tool wear in the process.
手打的,可能有错误,如果看上去桔子实在不同请看下图,不要求100%精确.

在超声加工,金属去除率的影响,其中有向扑来工件表面多次在高频振荡磨料工具的帮助.该工具的横截面是相似,但所需的形状孔只有它是一个小规模较小,以弥补在这个过程中过切.该工具振荡在15千赫到30千赫的频率与顺序从0.1毫米至0.3毫米的幅度.磨粒之间进行的工具和载体与一个流体,一般水帮助工件的差距.料浆循环也带走了破旧的谷物和加工碎片,并取代他们的工件,该工具也得到大小由于磨料切削作用的降低.因此,通过超声波加工螺纹孔钻,即在顶部大.通过补偿刀具磨损正常,紧密公差可以得到.
图18 - 4显示了USM的设备示意图.它由一个振荡器,转换成50赫兹的高频电源（15 kHz至30 kHz）的权力,进而转换成机械振动与磁致伸缩或压电换能器的帮助.在这两种类型,压电换能器的效率更高,也就是说,它们涉及较少失去权力,因此不需要冷却.一般在老机器中发现的磁致伸缩换能器效率较低,由于涡流损耗高,因此可能需要冷却.
现代机器的额定功率从0.06变化到四千瓦部分设计有等级甚至达到二○千瓦
应用
这个过程已经被成功地用于下列应用.
（1）为硬而脆,无法用常规方法加工材料的加工.难加工材料包括玻璃,金刚石和硬质合金等金刚石拉丝模,钨硬质合金通过使用USM的过程中钻.
（2）为圆形和非圆形孔加工直或弯曲的轴.
（3）硬质材料线程.这可以通过有适当的工具和工件的议案.
（4）它也被成功地用于加工的天竺葵,硅,陶瓷,碳板,石英,工具钢,合成红宝石,等使用
（5）对于非圆形孔钻硬质合金.
限制
这一过程的主要限制如下：
（1）低加工率达到相比,传统的加工工艺.
（2）这是非常困难的深洞机器,因为泥浆运动受到限制.
（3）它是很难设计的工具,在工作中获得精确的尺寸正确的大小.
（4）有高的过程中刀具磨损.
如果,你那里错了,我这里也就错了