Features and potentialities of USM

2019-11-29 09:14:18

Technician classified workpiece materials into three categories in consideration of the USM suitability: the materials belonging to the first group, such as glass, mica, and quartz, are quite brittle and easy for USM process. The materials are removed by the initiation and propagation of tiny cracks of the workpiece in this situation. The second group includes the materials that exhibit some plastic deformation before fracture like titanium alloys, carburized, and nitrided steels. USM can machine these materials although with some difficulty. The last group consists of the ductile materials, such as soft steel and copper, and they are unsuitable in principle for USM. Note that a recent research reported that the ductile substrate materials are not really removed but are displaced, which also have been observed for some fine polishing operations. The classification of the materials and fields of application for USM are given in Table 1.

 Group of material  Predominant type of deformation  Type of failure Field of application of USM 
 Glass, mica, quartz, ceramic, diamond, germanium, silicon, ferrite, alsifer  Elastic  Brittle  Manufacturing parts of semiconducting materials
Making industrial diamonds
Fabricating special ceramics
Manufacturing parts of glass quartz or minerals in the optical and jewelry industries
Machining ferrite, alsifer, and other materials
 Alloys tempered to high hardness carburized and nitrided steels, titanium alloys  Elastic–plastic  Brittle after work hardening by plastic deformation  Making and repairing hard alloy dies, press tools, and purchases
Shaping or sharpening hard alloy tools
 Lead, copper, soft steel  Plastic  No failure (or ductile failure)  Unsuitable for ultrasonic machining

USM has shown potentialities in many manufacturing uses; the most commonly ones are the fabricating structures of any shapes on hard and brittle materials. Hole drilling always stands as the most popular machining process for product manufacturing, and USM in particular shows a high potentiality in fabricating diverse holes either with large/small diameters or high aspect ratios. Technician’s group firstly proposed micro-USM as an effective micromachining process for hard and brittle materials. Holes with diameters as small as 5 μm and aspect ratios larger than 5 were successfully fabricated on quartz glass and silicon by micro-USM in one of their studies. At the other extreme, tools with diameters as large as 85 mm were successfully employed for drilling holes with a high-capacity (2.5 kW) ultrasonic machine. Besides, USM is playing an irreplaceable role in fabricating holes with a high aspect ratio. Micro-holes under 100 μm in diameter and aspect ratios of 10 on quartz glass were achieved by electrorheological fluid-assisted USM.

PreviousIntroduction of Ultrasonic Machining

NextTraditional Cutter and Ultrasonic Cutter