Surface Quality Investigation of Nanoparticle Colloid Hydrodynamic Cavitation Jet Polishing Technology

Abstract

Nanoparticle colloid hydrodynamic cavitation jet polishing (HCJP) is a supersmooth surface machining technology that utilizes the interface reaction to remove material from workpiece, applying the cavitation effect to improve the processing efficiency. In this paper, a plototype equipment of HCJP is introduced and the experiment of HCJP and common jet polishing has been done. The experiment results indicate that in both cases, the processed area presents the orbicular structure of “W” shape when the angle of jet and horizon is 90°; the position that has the best surface quality located on the annulus of processing region where the most material removed. Compared with the common jet polishing, the surface quality processed by HCJP that uses the swirling jet is better. In processing experiment of HCJP, the supersmooth surface with roughness of Ra 0.758nm is obtained.

Technology of Latent Heat Storage for High Temperature Application: A Review

“…72,[76][77][78] In contrast, micro-encapsulation of PCM has recently attracted considerable attention [79][80][81][82][83][84][85] because it reduces the reactivity of the PCMs with the outside environment, increases the heat transfer area of the PCMs, and enables the core material to withstand frequent changes in the volume of the storage material during phase change. Table 4 lists trends in manufacturing methods for PCM capsules.…”

“…Many papers have reported the production of various microcapsules, and the manufacturing methods, core PCM materials, shell materials, thermophysical properties, and capsule sizes of the same have been studied. Micro-interfacial polymerization, 80) in-situ polycondensation, [81][82][83][84][85] and complex coacervation 79) are the most popular microen- ISIJ International, Vol. 50 (2010), No.…”

“…Many papers have reported the production of various microcapsules, and the manufacturing methods, core PCM materials, shell materials, thermophysical properties, and capsule sizes of the same have been studied. Micro-interfacial polymerization, 80) in-situ polycondensation, [81][82][83][84][85] and complex coacervation 79) are the most popular microen- 52) proposed the encapsulation of spherical metal PCMs such as Cu and Pb with an electroplated Ni layer to recover industrial hightemperature waste heat such as combustion offgas. The PCM spherical capsule with Ni coverage provided hybrid functions of both heat storage and catalysis.…”

Fabrication of electrospun nonwoven mats of polyvinylidene fluoride/polyethylene glycol/fumed silica for use as energy storage materials

“…Microcapsules are particles with a wide range of sizes, that is, submicron‐sized to several micron‐sized particles; in these microcapsules, the PCM is enclosed by a thin polymer film. 8–11 Because of their small diameter of the microencapsulated particles, these microencapsulated particles have a high‐surface‐area‐to‐volume ratio, and their thermal conductivity is well enhanced. 12 Sari et al 13 reported that n ‐octacosane‐containing poly(methylmethacrylate) (PMMA) microcapsules prepared by emulsion polymerization have good thermal and chemical stability and that the phase change temperature and enthalpy show no significant change even after 5000 heating/cooling processes.…”

Research on Processing Efficiency and Contact Characteristics of M300 Steel Surface Grinding with Elastic Abrasives

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