This paper deals with the optimization of external roller burnishing operation using a CNC lathe for a Mg-SiC metal matrix. Magnesium metal was alloyed with 10% (w/w) of SiC particles as a reinforcement. The Stir casting process was used to cast the bars. CNC turning was then performed on these bars to prepare them for the roller burnishing process. The process parameters considered during burnishing are speed, feed rate, force and number of tool passes. Surface roughness, microhardness and out of roundness were the outputs of each experiment. The Taguchi methodology was used to design an experiment. This design yielded an L16 (44) Matrix. Response Surface Methodology was then used for procuring the optimized set of process parameters. Surface plots were studied to understand the impact of all the potential combinations of the process parameters. Regression equations were formulated between the input and output parameters. The optimum surface roughness of 0.1506 μm, surface hardness of 57.9996 HV and out of roundness of 0.0151 mm were obtained from the following burnishing parameters: speed of171 rpm, feed rate of 0.18 mm/rev, force of 21 N and 3 passes. The optimized parameters were found with the desirability factor of 0.9991.

Optimization of external roller burnishing process on magnesium silicon carbide metal matrix composite using response surface methodology


 In the precision fabrication industries, ultrasonic vibration assisted grinding is widely utilized for the finishing of “difficult-to-cut” materials due to its intermittent cutting mechanism and brittle-to-ductile mode machining. In this study, a 2D finite element model (FEM) of single grit ultrasonic vibration assisted dry grinding (UVADG) and conventional dry grinding (CDG) of AISI D2 steel has been developed, which taken into account the influence of longitudinal ultrasonic vibration on the workpiece with variable downfeed. The effects of ultrasonic vibration and downfeed on the chip formation mechanism, temperature field, grinding force and equivalent stress and strain were evaluated by analytical and simulation methods. The results show that the formation of the grinding chips under UVADG is much shorter and straighter than CDG mode at all respective downfeed. The validation experiment compared the simulated and experimental grinding force in both grinding modes to verify the reliability of the FEM results. The validation results demonstrate that the FEM model can accurately describe the single grit UVADG and CDG grinding. At each downfeed, the CDG mode has generated a larger equivalent plastic strain than the UVADG mode, resulting in a higher thermo-mechanical load on the workpiece. According to the findings, UVADG mode has least plastic damage on the ground surface, which may improve the surface integrity of the ground component.

Modelling and simulation study of dry ultrasonic vibration assisted grinding of tool steel with single alumina abrasive grit

Analytical Modeling of Machining Forces and Friction Characteristics in Ultrasonic-Assisted Turning Process

A novel ultrasonic burnishing (UB) system with a flat tool using a piezoelectric longitudinal transducer (PLT) is proposed. High-precision no-feeding mark planar burnishing can be achieved by the compact system with a size of only 280 × 224 × 558 mm without the need for machine tools. Above all, the structure of the burnishing system is presented and the operation principle is analyzed in detail. A resonant frequency design method of the PLT with a tool head is discussed. Based on this, the PLT achieves the expected resonant frequency precisely. Subsequently, the test system for the PLT is built and the resonant frequency and vibration amplitude are tested, which are in good agreement with the simulation results. Ultimately, the UB experiments are carried out and the results indicate that the surface roughness of the workpiece is reduced from Ra 1.6 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">μ</i> m to Ra 0.182 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">μ</i> m, which is reduced by 88.31%. Furthermore, the surface topography shows that the surface without the feeding mark is generated, which is beneficial to improve the burnishing accuracy and expand the application in ultra-precision processing. 

A Compact Ultrasonic Burnishing System for High Precision Planar Burnishing: Design and Performance Evaluation

The invention discloses a tool head integrating pressure control and displacement compensation and a control method. The tool head comprises a knife handle sleeve, a lifting knife handle, a tool headbody and a T-shaped threaded rod, wherein one end of the tool head body is fixed at the bottom of the lifting knife handle, and the other end of the tool head body extends out of the lifting knife handle; a thread is arranged in the lifting knife handle, and the thread is matched with the screw rod part of the T-shaped threaded rod; the top of the T-shaped threaded rod is located in the knife handle sleeve, and the T-shaped threaded rod divides the inner cavity of the knife handle sleeve into an upper rodless cavity and a lower rodless cavity; the upper rodless cavity is connected with an airpressure control system; and gear teeth are arranged on the outer ring of the lifting knife handle, the gear teeth are matched with three gears, and a gear shaft of each gear is driven by a motor.

Tool head integrating pressure control and displacement compensation and control method

\n Ultrasonic burnishing is usually applied to make machined surface modification. The acoustic softening effect caused by ultrasonic vibration is beneficial to the machining of difficult-to-cut materials. In the present work, a burnishing force prediction model was proposed for rotary ultrasonic burnishing of titanium alloy Ti–6Al–4V, whose surface had been machined with the face milling process. Firstly, the contact between the burnishing roller and one single milling mark was analyzed with plane strain assumption based on the Boussinesq–Flamant contact problem. Then, the effect of ultrasonic softening on the yield stress of Ti–6Al–4V was investigated. The critical contact width and contact load that the burnishing roller crushed on one single milling mark were examined to confirm the feasibility of the proposed ultrasonic burnishing force prediction model. The experimental verifications were carried out at various ultrasonic powers. The burnishing forces from experiment measurements were consistent with the calculated results from the proposed model. The mean deviations between theoretical and experimental results of the ultrasonic burnishing force were 10.4%, 12.2%, and 15.2%, corresponding to the ultrasonic power at the level of 41 W, 158 W, and 354 W, respectively.

Analytical Prediction and Experimental Investigation of Burnishing Force in Rotary Ultrasonic Roller Burnishing Titanium Alloy Ti–6Al–4V

Micro-texturing on machined surface has been widely applied to improve surface friction and wear properties. This paper aimed at establishing a relationship among process parameters, machined surface texturing, and friction property of scaly surface fabricated by rotary ultrasonic rolling. Firstly, a kinematic model of the scaly surface topography formation was proposed based on motion analysis between the roller and workpiece. Secondly, the roller profile was considered in the proposed model to describe the scaly surface topography formation. Three-dimensional surface roughness characteristic parameters Sa, Sz, and Sq were adopted to evaluate the scaly surface topography. These three-dimensional surface roughness parameters can be theoretically predicted with the proposed kinematic model for the scaly surface fabricated by rotary ultrasonic rolling of titanium alloy Ti-6Al-4V. The theoretical predictions of Sa, Sz, and Sq were verified with the experimental results. Finally, the friction coefficients of scaly surfaces generated with various rotary ultrasonic rolling parameters were tested. The friction coefficient of the scaly surface was minimum at ultrasonic amplitude of 7 μm. The results demonstrated that the surface texturing with larger scaly ridges possessed improved frictional performance under identical test conditions.

Surface texture and friction property of Ti-6Al-4V processed by rotary ultrasonic rolling

The invention relates to a rolling pressing processing device capable of monitoring pressure and a cutter track online and a method thereof The device comprises a cutter cover, a locking cushion andcutter head assemblies, wherein one end of the cutter cover is mounted on a cutter handle while the other end of the cutter cover is fixedly connected to the locking cushion; a plurality of cutter head mounting grooves are formed in the cutter cover; through holes which are corresponding to the cutter head mounting grooves are formed in the locking cushion; the cutter head assemblies pass throughthe through holes to be mounted into the cutter head mounting grooves; propping pushing mechanisms for propping and pushing the cutter head assemblies to move are arranged in the cutter head mountinggrooves; and the displacement of the cutter head assemblies is monitored through a displacement monitoring device The device is high in processing efficiency, and high in accuracy, and is capable ofprocessing planes and different types of groove surfaces by rolling and pressing

Rolling pressing processing device capable for monitoring pressure and cutter track online and method thereof

The invention discloses a damping face milling cutter with adaptive instantaneous change of a tooth pitch and a cutting speed The damping face milling cutter comprises a cutter body, a flange, a plurality of indexable cutters, a spring and a mounting cutter handle; the cutter body comprises an outer cutter body, an inner cutter body and a bearing for connecting the outer cutter body and the innercutter body; the outer cutter body is located on the outer side of the cutter body, the inner cutter body is located on the inner side of the cutter body, and the indexable cutters are alternately connected with the inner cutter body and the outer cutter body; the flange is connected to the cutter body, and the spring is located between the flange and the cutter body; and the mounting cutter handle is connected with the cutter body The damping face milling cutter with adaptive instantaneous change of the tooth pitch and the cutting speed can suppress the generation of self-induced vibrationduring cutting, and has a variable pitch cutting edge and a modulatable cutting speed

Damping face milling cutter with adaptive instantaneous change of tooth pitch and cutting speed

The invention discloses a plane milling-rolling composite device and a milling machine comprising the plane milling-rolling composite device The plane milling-rolling composite device comprises a shell An installation tool handle used for being connected with an external power device is arranged on the shell The installation tool handle is coaxially connected with a tool apron of a milling tool body The milling tool body is installed on the tool apron of the milling tool body The rotation movement of the tool apron of the milling tool body is transmitted to a tool apron of a rolling tool body through a transmission device The axis of the tool apron of the rolling tool body is parallel to the axis of the tool apron of the milling tool body, and the axis displacement of the tool apron of the rolling tool body is further adjusted through a displacement adjusting device The transmission device is further provided with a transmission rod adjusting device adjusting the axis distance of the milling tool body and the rolling tool body

Zhao Jian

Papers

Analytical Prediction and Experimental Investigation of Burnishing Force in Rotary Ultrasonic Roller Burnishing Titanium Alloy Ti–6Al–4V

Surface texture and friction property of Ti-6Al-4V processed by rotary ultrasonic rolling

Rolling pressing processing device capable for monitoring pressure and cutter track online and method thereof

Damping face milling cutter with adaptive instantaneous change of tooth pitch and cutting speed

Plane milling-rolling composite device and milling machine comprising plane milling-rolling composite device