Study of Micro Rotary Ultrasonic Machining

Product miniaturization for applications in fields such as biotechnology, medical devices, aerospace, optics and communications has made the advancement of micromachining techniques essential. Machining of hard and brittle materials such as ceramics, glass and silicon is a formidable task. Rotary ultrasonic machining (RUM) is capable of machining these materials. RUM is a hybrid machining process which combines the mechanism of material removal of conventional grinding and ultrasonic machining. Downscaling of RUM for micro scale machining is essential to generate miniature features or parts from hard and brittle materials. The goal of this thesis is to conduct a feasibility study and to develop a knowledge base for micro rotary ultrasonic machining (MRUM). Positive outcome of the feasibility study led to a comprehensive investigation on the effect of process parameters. The effect of spindle speed, grit size, vibration amplitude, tool geometry, static load and coolant on the material removal rate (MRR) of MRUM was studied. In general, MRR was found to increase with increase in spindle speed, vibration amplitude and static load. MRR was also noted to depend upon the abrasive grit size and tool geometry. The behavior of the cutting forces was modeled using time series analysis. Being a vibration assisted machining process, heat generation in MRUM is low which is essential for bone machining. Capability of MRUM process for machining bone tissue was investigated. Finally, to estimate the MRR a predictive model was proposed. The experimental and the theoretical results exhibited a matching trend.

RP96-11 The Farm Corporation: What It Is, How It Works, How It Is Taxed

A corporation is an artificial person that is created and operated according to state corporation statutes. It is a separate taxpayer subject to specific and detailed federal, state, and local tax laws. The advice and service of your lawyer are indispensable in organizing and operating a farm corporation. There are three basic forms of farm business organization, the sole proprietorship, the partnership, and the corporation. Variations of these forms have resulted in the limited partnership and the "tax option" corporation. These three basic forms are discussed in this research publication.