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The purpose of this paper is to measure the effect of rake angle on cutting forces on the rake face of single point cutting tool with two cutting conditions. The experimental setup has been developed to measure the cutting forces. The study aims to put forward the optimum cutting condition, which improves the product quality, surface finish, productivity and tool life.

The load cell-based tool dynamometer has been developed to measure the cutting forces. The experiments have performed on the mild steel bar of hardness 60 BHN. The friction and the normal forces have measured in dry cutting condition and with rust-X cutting fluids. The cutting forces for these two cutting conditions have calculated with constant depth of cut, speed and feed with different rake angles in the range of degrees 6, 7, 8, 9, 10, 11, 12, 15 and 20.

The experimental observations shows the variations of friction and normal forces with different cutting conditions and parameters. It shows the friction force on rake face increase and the normal force on the rake face decreases with increase the rake angle.

The observations has done only for mild steel of hardness 60 BHN. It can also be perform on different materials and for different cutting conditions.

The experimental setup developed in this research can be used in the manufacturing industry. It can help to decide and maintain the optimum cutting conditions.

The observations have been made on an experimental setup, which fulfills the actual working/cutting conditions as per the use in industries.

The purpose of this paper is to determine the optimum level of geometrical parameters such as helix angle, nose radius, rake angle and machining parameters such as cutting speed, feed rate and depth of cut to arrive minimum surface roughness and tool wear during end milling of Al 356/SiC metal matrix composites (MMCs) using high speed steel end mill cutter.

L27 Taguchi orthogonal design with six factors and three levels is employed for conducting experiments. Analysis of variance (ANOVA) is carried out using Minitab16 software to find the influence of each input parameter on output performance measure. Grey-fuzzy logic multi optimisation algorithm is used to find the optimum level of the input parameters for minimum surface roughness and tool wear simultaneously.

It is found that optimal combination of helix angle 40°, nose radius 0.8 mm, rake angle 12°, cutting speed 90 m/min, feed rate 0.04 mm/rev and depth of cut 1.5 mm have generated minimum surface roughness of 0.4063 µm and tool wear of 0.0375 mm. From ANOVA analysis, it is found that cutting speed influence is more on output performance followed by helix angle and rake angle compared with other machining and geometrical parameters.

The influence of tool geometry during end milling of MMC using Grey-fuzzy logic algorithm has not been explored previously.

The purpose of this paper is to find out the optimal level as well as the influence of end mill cutter geometrical and machining parameters while machining metal matrix composite. End milling is carried out on Al 356/SiC metal matrix composites (MMC) using high-speed steel (HSS) end mill cutter. The optimum level of input parameters such as helix angle, nose radius, rake angle, cutting speed, feed rate and depth of cut are calculated for minimum temperature rise.

L27 Taguchi orthogonal design, signal-to-noise (S/N) ratio, are applied for conducting experiments, and to find the optimal level of input parameters for minimum temperature rise, respectively. Analysis of variance (ANOVA) is used to analyze the significance of input parameters on temperature rise.

It is found that the optimal combination of helix angle 400, nose radius 0.8 mm, rake angle 80, cutting speed 30 m/min, feed rate 0.04 mm/rev and depth of cut 0.5 mm have generated minimum temperature rise. From ANOVA analysis, it is found that rake angle influence is more on output performance followed by cutting speed and nose radius compared with other machining and geometrical parameters.

The influence of geometrical parameters such as helix angle, nose radius and rake angle of end mill cutter on temperature rise while machining MMC has not been explored previously.

THE FUNDAMENTAL principles governing the behaviour of aircraft during steering manoeuvres on the ground are now well known and documented, but one particular aspect of the problem has not, to the writer's knowledge, been dealt with in the literature. This article examines this feature and describes methods for evaluating its effect on the overall steering power requirements and system behaviour. The influence of tyre characteristics is also examined.

FROM a machinability aspect, stainless steels may be classified into three categories, the general analysis of which influences the machinability factor.

THE considerations involved in the successful machining of aluminium and its alloys have sprung into particular prominence during the last year or so with the greatly increased use of these materials under the armaments expansion programme. Numerous firms who have hitherto confined their attentions to steels and non‐ferrous metals like brass and copper arc now engaged in the mass production of parts machined from extruded, rolled and cast aluminium and aluminium alloys. These light metals are by no means difficult to machine but their particular properties require a special technique if full advantage is to be taken of the economy resulting from the high speed at which they may be worked.

In any machining process, the surface profile of the workpiece is continuously changing with respect to time and input parameters. In a conventional machining process, input parameters are feed and depth of cut whilst other parameters are considered to be constant throughout the process.

The direct and indirect participation of this instantaneous curvature can be used to optimize the strategy of cutting operation in terms of different parameters like heat generation-induced stresses, etc. The concepts of the metric tensor and Riemannian curvature tensor are made use in this study as a representation of curvature itself. The objective of this study is to create a mathematical methodology that can be implemented on a highly flexible machining process to find an optimum cutting strategy for a particular output parameter.

The study also includes different case studies for the validation of this newly introduced mathematical methodology.

The study will also find its position in other mechanical processes like forging and casting where instantaneous curvature affects various mechanical properties.

THE aerospace industry probably presents more machining problems in general than any other single industry. There are more high precision components found in aircraft than in most engineered equipment and a greater use of difficult to work exotic materials.

The second in a series giving suggestions for laboratory work on the various types of machine tool

Developing countries are now fully aware of the importance of the manufacturing sector as a key factor of growth and transformation of their economy. Improved technology and method of manufacturing have produced quality products at reduced cost and this has advanced development. The study uses experimental methods based on orthogonal cutting process to measure the cutting forces using a dynamometer while machining the test specimen with a diamond cutting tool at 5° rake angle. The machining forces for the dry cutting are higher than the wet cutting in the range of 31.2‐44.31, 32.09‐40.67, 29.10‐35.62, 29.21‐45.03 and 29.94‐38.74 percent for “as received”, normalized, tempered, annealed and hardened specimen, respectively. For annealed and hardened test specimen, the cutting speed of 245 rpm is ideal for machining when it gives a fine surface finish. Also for precision machining, dry turning is by far a better cost saver and cleaner option than wet turning. This is because though wet machining is relatively more expensive, it is hazardous to health. Normalized and annealed specimens require lower cutting forces and chip formation is slow. Tempering and annealing medium carbon steel facilitated rapid machining and chip formation is rapid. It is therefore an advantage to temper or anneal medium carbon steel before processing into component parts in the manufacturing industry as it saves cost and gives fine component surface finish. The paper aims to address these issues.

Tensile samples are prepared from medium carbon steel. These prepared samples were later subjected to heat‐treatment operations (normalizing, hardening, tempering and annealing). Tensile test were carried out to obtain the materials' sensitive properties used in the modeling equations. An experimental method based on orthogonal cutting is adopted to measure the machining forces using techquipment dynamometer.

It is observed that as t_u increases, F_c increases for all conditions, i.e. as t_u increases, tool‐chip contact area increases and increasing frictional force, also volume of metal removal increase resulting in increasing energy input. F_c values is highest for the normalized followed by that of the annealed. They are less for hardened and tempered. This is because of the mode of chip formation whereby ductile structures give continuous chips as against discontinuous structure for the hardened and quenched structures. Input energy is high for the former and low for the later. This is confirmed by the m values and observed chips.

There is no limitation, except for the instrumentation. On availability of the appropriate equipment, like the Kystler dynamometer for the correct reading of the experimental results.

The implication is limited to the workshop hazard during the experiment.

The research work is original.