The grinding surfaces of the nickel-based superalloy usually generate tensile residual stress, which may reduce fatigue life components. In order to transform stress compressive this research develops a new technology that embeds heat source inside workpiece during grinding. process Inconel718 is simulated by using COMSOL Multiphysics 5.0, and distributions with without added are obtained. addition, influence density source, length height distance between zone on studied. results as follows:...

Water jet peening (WJP) is a mechanical surface strengthening process, which can improve the residual stress (RS) of peened and then fatigue life components. In this paper, erosion experiments are conducted to investigate influence parameters on erosion. On basis, RSs induced by WJP studied in relation parameters. addition, coupled Eulerian–Lagrangian (CEL) technique used model simulate dynamic impact process Al6061-T6. The such as pressure p, traverse velocity vf, number water pass n...

Abrasive waterjet (AWJ) peening can be used for metal surface strengthening by introducing near-surface plastic strain and compressive residual stress. The present studies seldom focus on stress AWJ of targets with different geometrical features. In fact, those usually exist some machine parts including gear roots, shaft shoulders, concentration areas. According to Hertz theory contact Miao's theoretical model predicting flat surface, this paper developed a investigating features concave arc...

A novel peripheral milling process with an end cutter for manufacturing aluminum fibers is proposed. Most of the cutting done by teeth and chips removed form fibers, while has little effect on fibers. The machining principle formation mechanism fiber cross-section are presented. feasibility this new fabrication experimentally investigated under different conditions. In addition, influences parameters equivalent diameter, length, surface morphology analyzed. Experimental results indicate that...

The water jet peening (WJP) technology can induce compressive residual stress (RS) in metal surfaces and, thus, improve the fatigue life of components. In this paper, a mathematical model is proposed for calculating RS induced by WJP. To validate model, experimental and finite element simulation verifications were carried out on Al6061-T6. distribution along depth direction, maximum RS, layer also investigated based model. Results showed that error between experiment was within 9% under...

This article reveals the formation mechanism of surface topography and coupling residual stress field (RSF) after abrasive water jet sequential peening (AWJSP) that can on material at a certain distance interval, proposes mathematical model dimple characteristic verified by simulation results. In addition, influences shot velocity v0, radius R between center adjacent shots DC RSF were also investigated. Results show forms resulting from plastic strain, (RS) is mainly induced unrecovered...

In this paper, the theoretical models of surface topography and residual stress (RS) were proposed, abrasive water jet sequential peening (AWJSP) finite element established by using ABAQUS. Then, formation mechanism in multiple passes AWJSP process coupling RS a single analyzed. After that, influence number shots (i.e. N), distance between center adjacent D c , shot velocity v, radius R on field (RSF) target investigated. Results show that successive dimples formed single-pass AWJSP, RSF...

A new method for fabricating CCMPMPs, namely multi-cutter milling, is proposed and the fabrication principle discussed. Then, a study of three microchannel parameters, depth Hc, width Wc, interval Ws, two CCMPMP porosity P total surface area per unit volume SV, presented. Furthermore, 3D FEM has been adopted to effective stress distribution, metal flow velocity cutting forces. The results show that CCMPMPs can be successfully machined. Ws controlled by radial cut ae, slotting cutter...

Abstract Pneumatic shot peening is a widely used surface strengthening method. During the process, shots often collide with each other, resulting in large energy loss and small compressive residual stress. In order to achieve optimum stress as little possible, firstly collision mechanism of forming coupling target’s are revealed, then pneumatic simulated by using DEM-FEM model. Then, effects impact angle θ , initial velocity v 0 diameter d p mass flow rate r m on percentage η different...

Abstract Water jet peening (WJP), a surface modification technique, can use the impact pressure induced by shock waves to introduce compressive residual stress in of metal parts, thereby improving fatigue life especially has broad application prospects strengthening concave area parts. The is different compared with flat due effects geometrical factors on wave released. In this work, mathematical model for calculating peak initial contact developed, and geometric (opening angle V α spherical...

In order to enhance the heat transfer performance of a plate exchanger, porous copper fiber sintered sheets (PCFSSs) with three-dimensional (3D) network structure has been developed. Slim fibers are manufactured new type multi-tooth tool. Then, they pressed and in designed mold produce PCFSSs. addition, pressure drop exchanger investigated experimentally. The results show that rough surface can be efficiently. PCFSFs 3D successfully machined. Moreover, PCFSSs porosity 70% nearly quadruple...

In the process of machining rectangular microchannels, severe friction occurs between chip and side face machined microchannel. The cutting forces have great effect on miniature tool. Thus, 3D FEM is adopted to study forces. influences depth microchannel t , a c width w rake angle ○ o speed ν are investigated. Results show that main force F z thrust y increase with no obvious change ν. Moreover, decreases increases as γ○ increases.

An efficient polishing process has been carried out at the speed about 200 mm/s in vacuum with temperature of 850˚C. With time reaches 120min, surface roughness polished could get to Ra0.016 compared original Ra9.67. Mass loss rate per hour was used quantify efficiency. Increasing pressure high mass rate, which be rough machining process. In fine process, should lower and remained. The 3D morphology from atomic force microscope(AFM) shows there are some summits 30-40nm height, take into...

In order to develop a rectangular corrugated microchannel (RCM) heat sink with high transfer and low pressure drop, is designed simulated, then the effects of amplitude <i>A</i>, wavelength <i>λ</i>, inlet flow velocity <i>u<sub>in</sub></i> on performance, Dean vortices, drop are investigated. Furthermore, <i>A, λ</i>, optimized according performance evaluation criterion (PEC). Moreover, effect number...