Effect Of Thrust Force Research Articles

Analysis of Drilling Behaviour in Jute Fibres Reinforced Natural Composites

ABSTRACT In the study, Natural jute composite materials, which have environmental advantages due to their easily degradable nature were drilled with different processing parameters and the effects of thrust force, vibration and temperature changes on hole quality were investigated. The effect of feed and spindle speed was statistically analyzed using ANOVA method. The thrust force, vibration and temperature factors that occur depending on the drilling parameters vary and affect the roughness and delamination values. The effect of feed and speed on thrust force was calculated as 97.87% and the feed effect (90.85%) is far greater than the speed (9.15%). The effect of drilling parameters on vibration is statistically insignificant due to the different spread behavior in the layers of the composite material (R2 = 0.2329). However, feed effect on vibration (94.6%) is greater than the speed effect (6.06%). The temperature is affected by 96.93% of the drilling parameters and the speed is 84.16% and the feed is 15.83%. The roughness effect depending on the drilling parameters is measured as 84.91%. The effect of speed on roughness (90.26%) is greater than the feed (9.73%). It has been determined that this situation is mostly related to vibration and temperature.

Effect of thrust force, torque, and induced temperature on Kevlar reinforced composites during drilling process

The present study aims at finding optimum drilling process parameters to reduce thrust Force and torque. Heat induces in drilling zone during drilling process has analysed by thermal image camera. The kevlar 49 reinforced epoxy composite specimen has utilized for experiments. Drill bits utilized for the experiments namely, Twist, Core, step cone, and candle stick. According to the experiment results feed rate is most influencing on thrust force followed by torque. A core and candlestick drill bits has produced lesser thrust force compared to other drill bits. Heat generated in drilling zone during drilling process has higher for step cone and standard twist drill bits compared to glass transition temperature of matrix. Hence, matrix has not able to providing necessary support to fiber in composite. Candle stick and Core drill bit has been providing lesser thrust force, torque and defect free machining at lower spindle speed and feed rate.

Effect of Thrust Force and Torque Analysis on Chemically Treated Kevlar Reinforced Composites during Drilling Process

Composites applications are widely used in many areas. Due to the enhancement of various properties. Now a days kevlar composite has widely used because of various properties like tensile , compression, shear. Drilling is the majority important machining process in making assembly of components within a negligible tolerance. Drilling in kevlar composites is difficult due its extradionary mechanical properties like high toughness and hardness. Thrust force and torque are the major influences for delamination during various machining of reinforcement polymer composites. Various paramaters are considered to reduce defects like delamination and fiber crushing. It is found from various literature reviews surface modification has enhancing the intermolecular bonding strength between fiber reinforced layers. Our paper deals with affect of process parameters on thrust force with respect to torque during drilling of Kevlar composites with and without chemically treated fibers. The composite lamina is prepared for the investigation of 60/40 kevlar-polyester resin on weight basis. The chemicals are used to treat the fibers such as Dichloromethane, methanol and distilled water with specified intervals of time. Twist and core drill bits are used to make holes. Results suggested that twist drill with chemically treated fiber having minimum thrust force. Our aim to identify the minimum delamination of composites.

Micro-drilling characteristics of sequential glass fiber-reinforced resin-based/copper foil multi-layer sheets

High frequency printed circuit board (HFPCB), a sequential glass fiber-reinforced resin-based/copper foil multi-layer sheet, is widely used as printed circuit boards in next-generation 5G communication base stations, radar antenna, smart cars, etc. Micro-holes are key components that enable the interconnections of different layers, fixed electronic components, and high-density wiring. However, hole wall debris and micro-drill breakage during the micro-drilling of sequential glass fiber-reinforced resin-based/copper foil multi-layer sheet negatively affect the quality and reliability of signal transmission. Herein, chip removal, chip morphology, drilling temperature, thrust force characteristics, and hole wall morphology of HFPCB micro-drilling are investigated. The effect of chip morphology on chip removal is analyzed. Additionally, the effects of thrust force and micro-drill breakage are analyzed. The formation mechanism of hole wall debris is proposed. Compared with traditional FR4, the fracture mechanism and control method of micro-drill breakage are proposed by analyzing the characteristics and cause of typical thrust force variations. Results show that the drilling temperature and chip removal of HFPCB are primary factors causing hole wall debris. The morphology of HFPCB chips primarily includes the chips of copper foil, agglomerate chips of resin layer, and mixed copper-foil–resin chips. The increase in prepreg, resin content, and number of multi-layers causes a large amount of cutting heat during HFPCB micro-drilling. Meanwhile, the large thickness, large depth ratio, and diameter resulted in poor chip removal. Subsequently, the constant accumulation of heat in the hole resulted in resin melting, followed by adhering to the hole wall, thus generating hole wall debris through a thermo-mechanical coupling extrusion. The long-term fluctuation of thrust force is the main reason for micro-drill breakage during micro-drilling.

The Effect of Thrust Force in Drilling Composite Materials Using a New Step Core-Ball Drill

Compared with conventional metal materials, composite materials can sustain more loads under lower weight and lower space, which is more suitable to use in high strength environment for structure parts application in aerospace, military, transportation and leisure. The enormous aeronautical components and structures of composite materials require assembly and machining. Drilling is the most important making-hole process in the final assembly. However, conventional drill cannot avoid delamination in drilling composite materials effectively depending on tool geometry only. Delamination caused by drilling thrust has been showed as one of the most problematic defects after drilling composite laminates. Drilling of composite plates using a new step core-ball drill (NSCBD), which is a special drill to improve the chip flow and reduces the thrust force (delamination) at the exit of hole, is studied and compared to the traditional step core-ball drill (TSCBD). The thrust force of new step core-ball drill in drilling composite materials was investigated in this study. The theoretical analysis and experimental results show that the NSCBD can improve the thrust force (delamination) and efficiency than TSCBD in drilling composite materials.

The effect of thrust force in drilling composite materials using step core-ball drill

Composite materials have gained increasing popularity over the past few decades due to their superior mechanical properties, such as high strength-to-weight ratio, fighting against high temperature and corrosion resistance. The assembly of enormous aeronautical components and structures require the machining of composite materials. Drilling is the most important hole-making process in the final assembly. When drilling composite materials, a number of defects are generating. Delamination caused by drilling thrust has been showed as one of the most problematic defects after drilling composite laminates. With a pressing need for decreased delamination, many studies are turning more and more toward tool geometry and machining parameters. Drilling of composite plates using a step core-ball drill, which is a special drill to improve the chip flow and reduces the thrust force at the exit of hole, is investigated in this study. The experimental results found that the step core-ball drill was efficient in drilling of carbon fiber reinforced plastic (CFRP) and did not produce loading on the drill exit at the proper drilling conditions. The results obtained from this study feeding back for fundamental research efforts could steer future studies on the drilling composite materials in the most promising direction.

An Experimental Study on the Effect of Thrust Force on Motor Performance in Linear Permanent Magnet Synchronous Motors

In this paper, the effect of thrust force on motor performance in Linear Permanent Magnet Synchronous Motor (LPMSM) was investigated. This study was carried out as experimental and motor control method was used in scalar control. The effect of thrust force with the vertical and horizontal placement of permanent magnets (PMs) in the fixed part, which is called the secondary side (the PMs were placed in this section), was evaluated according to test results. Test results that have been obtained from computer program were given in the last part. According to test results, the horizontal placement of PM has a positive and significant contribution to the thrust force. In this context, motor performance has affected in a positive way.

Experimental Study of Helical Milling on CFRP (Carbon Fibre Reinforced Polymer) for the Hole Making Process

Generate borehole by helical milling process may be used effectively since accurate location of the hole may be secured by means of the feed screw graduations. Fiber delamination which is the main defect occurred during hole making process on carbon fiber reinforced polymer (CFRP) were investigate throughout an experimental study. Effects of thrust force (Fz), delamination factor (Fd) and surface roughness are evaluated. Objective of the experiment are to find best cutting parameter and tool design suitable to performed helical milling operation on CFRP. Two types of end mill with 4 flutes were used and results are evaluated. It was found that tool design 2-1 has higher performance on CFRP.

Mediating effects of wrist reaction torque on grip force production

A pistol grip, power tool simulator was developed and used to examine the mediating effects of wrist reaction torque on changes in direct measures of grip force. The effects of thrust force (0 and 45 N), and pre-existing grip force (10 and 30% MVC) were also controlled with this simulator. A modified Jamar dynamometer attached to the motor shaft, permitted grip forces to be measured directly. A 2×2×2×2, repeated measures ANOVA, was used to test the effects of torque impulse magnitude, duration, thrust force, and pre-existing grip force on changes in normalized grip force. Subjects included 11 males and 8 females. Grip force increased significantly (31–254%) with increasing torque magnitude. Grip force decreased (15–37%) with increasing pre-torque grip force. Grip force was not significantly affected by torque duration. Grip force also decreased 10–31% with increasing thrust force. Derived measures of hand-wrist dynamic compliance decreased significantly with increases in torque duration, thrust force, torque magnitude, and pre-torque grip force. The wrist actively stiffened under these conditions. Relevance to industry Manufacturers of powered hand tools may find this study useful to further their understanding of the effects of tool use on the hand–wrist system. The importance of torque shut-off mechanisms and a continued attention to optimal handle design is also supported by this work.