摘要:

A quantitative model considering signal attenuation and tool flank wear is proposed to describe the influence of machining process parameters on the level of acoustic emission (AE) generation. The AE sensitivities to width of cut, feed rate, and hardness of material in three-dimensional cutting are experimentally studied. The application of AE signal analysis to chip formation detection, providing information for process control in unattended machining, is described.

ISSN:0884-2558    

DOI:10.1080/10426918608953155

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Several parallel paths are being pursued in the further development of grinding processes. On the one hand, since higher material removal rates are to be realized, machines of greater rigidity with more efficient drives and tools are required. On the other hand, increasing demands are placed on the quality of machined parts. One trend is towards the utilization of super hard abrasives such as cubic boron nitride (CBN). Advantages of this grinding material as opposed to the conventional corundum are significantly greater hardness and, therefore, longer profile life, higher material removal rates, and lower grinding temperatures. One disadvantage is the price of the tool, which is several magnitudes higher than for corundum. Considering the high initial costs for CBN cutting material, destruction of the wheel caused by faulty operation of the machine or undue allowance must have the aim of transferring supervision and control tasks from the operator to the machine control. Fundamental for this concept are suitable sensor systems for monitoring the grinding process. A constant normal grinding force achieved by regulating the feed rate avoids clogging and destruction of the wheel. In addition, the grinding time is reduced, since the bending of the spindle can be compensated.

ISSN:0884-2558    

DOI:10.1080/10426918608953156

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Since Electric Discharge Machining (EDM) has been made available to industry, substantial improvements have been achieved from the point of view of overall machining efficiency throughout the last decades. Even by the fact that several classical machining methods are still more attractive in terms of machining speed, cost, and conveniency, “Deep Sinking” Electric Discharge Machining has its own application areas mainly in die making. In many cases, certainly for finishing and even polishing jobs, the preparatiion of the EDM tool is of the greatest importance. All the final geometrical information to be brought on the workpiece is initially present on the tool surface. It involves the final geometrical details of a three dimensional shape with accuracies up to a few μm. Spark erosion itself is a thermo-physical process dealing with electrical discharges occurring between an anode and a cathode. These sparks, which are randomly distributed all over the tool-workpiece contact area, have such a power density (105to 107W/mm2) that metal is removed by melting and evaporation.

ISSN:0884-2558    

DOI:10.1080/10426918608953157

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The basic tools of optics consist of a classical family containing lenses, scales, interferometers, and the myriad of instruments that make use of them. Their usefulness has been greatly enhanced recently by the addition of lasers as a light source, electronic detectors as replacement for the human eye, and computers to rapidly process results. A new tool has been the introduction of optical fibers — which is beginning to establish a new family.

ISSN:0884-2558    

DOI:10.1080/10426918608953158

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The design, development, and application of ultra-precision CNC machines for

ISSN:0884-2558    

DOI:10.1080/10426918608953159

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The Cranfield Unit for Precision Engineering (CUPE) specializes in the design, development, and construction of advanced, high precision CNC machines of many types. Two years ago, the British Science & Engineering Research Council (SERC) commissioned CUPE to develop and commission an ultra-precision CNC diamond turning machine for the manufacture of X-ray telescope mirrors up to 1400 mm in diameter and 600 mm in axial length. This vertical axis machine incorporates many novel design and manufacturing features. This paper describes the design and manufacturing philosophies and techniques used in bringing it to its present successful level of development.

ISSN:0884-2558    

DOI:10.1080/10426918608953160

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor