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Classification of Steel
Published in Vladimir B. Ginzburg, Metallurgical Design of Flat Rolled Steels, 2020
Surface finish refers to the degree of smoothness or luster of the surface as distinct from surface imperfections and requires a special preparation and control of the roll surfaces employed. Cold rolled sheet can be supplied in the following finishes [4]: Matte FinishCommercial Bright FinishLuster Finish
Additive manufacturing processes
Published in Fuewen Frank Liou, Rapid Prototyping and Engineering Applications, 2019
Once the first layer is complete, the platform is then lowered, a new layer of powder is uniformly distributed, and the process is repeated until the part is complete. The resulting part is close to fully dense. Finish heat treatment or machining may be used to improve the surface finish. Extremely complex internal geometry is the limiting factor of the EBM process. The EBM process may ultimately be applicable to a wider range of materials than competitive processes and also has the potential to offer much better energy efficiency. Some of its benefits include the ability to achieve a high-energy level in a narrow beam, vacuum melt quality to yield high strength properties of the material, and vacuum environment to eliminate impurities such as oxides and nitrides, and the ability to permit welding in refractory metals and combinations of dissimilar metals. Compared with laser melting, additional benefits include higher efficiency in generating the energy beam resulting in lower power consumption, lower maintenance and installation costs, the high actual overall power resulting in high build speeds, and the deflection of the beam to avoid moving parts resulting in high scanning speed and low maintenance.
Metallurgy for the Nonmetallurgist with an Introduction to Surface Finish Measurement
Published in Jerry P. Byers, Metalworking Fluids, Third Edition, 2018
Specifying surface finish is basically a process of describing the topography and texture of the boundary surface of a solid body in quantifiable terms. Surface finish is an important parameter of a component part. It determines how the part will respond to sliding friction, how well it will retain a lubricant, the wear rate that will be experienced, and how well it will retain a coating, such as electroplating or painting to name just a few. Surface finish measurement is also closely linked to dimensional tolerancing. It would be irrational to reference a very precise dimension from a very rough surface.
Structured Point Cloud Data Analysis Via Regularized Tensor Regression for Process Modeling and Optimization
Published in Technometrics, 2019
Hao Yan, Kamran Paynabar, Massimo Pacella
While surface shape represents the overall geometry of the area of interest, surface roughness is a measurement of the surface finish at a lower scale (surface texture). Surface roughness is commonly characterized with a quantitative calculation, expressed as a single numeric parameter of the roughness surface, which is obtained from a high-pass filtering of the measured surface after the shortest wavelength components are removed. In the reference case study, the measured surface is obtained from scanning the actual surface with a probe which mechanically filters this data due to the CMM tip radius (0.5 mm). Given the CMM measurements in the experiments, the variance of residuals after modeling the shape of cylindrical items is assumed as the quantitative parameter related to surface roughness.
Machinability analysis of high strength materials with Cryo-Treated textured tungsten carbide inserts
Published in Materials and Manufacturing Processes, 2019
D. Palanisamy, K. Balasubramanian, N. Manikandan, D. Arulkirubakaran, R. Ramesh
As the model is adequate these 3D surface plots can be used for estimating the surface roughness values for any suitable combination of the input machining variables. It is observed from Fig. 2(a) that the lower machining speed produces poor surface finish. It is also observed that the combination of higher machining speed and lower feed results better surface finish. Higher machining speed reduces tangential forces thus surface roughness is improved and high tangential force is produced at low speeds which deteriorates surface quality. Higher feed rate combined with higher machining speed can enlarge the cutting area and increase deformation resistance and improves the stability of the cutting process and it reduces the vibration produced during the machining process thus reduces surface roughness. It is clear from Fig. 2(b,c) that higher machining depth has a significant effect on the surface Roughness Ra.
Processing issues, machining, and applications of aluminum metal matrix composites
Published in Materials and Manufacturing Processes, 2018
Surface finish is important as it affects the fatigue resistance, wear, and corrosion resistance of machined part.[235] Increases in surface finish, increases fatigue resistance of the machined part.[235236237238239] Researchers recommended the study of surface roughness[229,240241242] of the machined part along with the tool wear study.[235] Machining of the materials generate geometric and metallurgical flaws on surface region.[182] Therefore, it is difficult to draw any conclusion merely from the tool wear study.[182] El-Gallab and Sklad[243] found a negative rake angle unfavorable for surface roughness. Clogging of the hot chips between tool and machined surface happens because of the negative rake angle.[243] Dabade et al.[244] and El-Gallab and Sklad[243] investigated the effects of cutting parameters and tool geometry on surface roughness of Al/SiC/10p. Cutting speed[245,246] and feed rate[246,247] considered dominant parameters for surface finish, whereas depth of cut[246,248] found nonsignificant parameter. Increase in cutting speed and reduction in feed rate enhances surface finish.[249] Moreover, constant feed with high cutting speed also improves the surface finish.[249,250]Figure 9 explains effects of feed and cutting speed on surface finish of HMMCs. Moreover, surface finish also depends on the amount of reinforcement.[49,251] Dabade et al.[244] observed reduction in surface finish as cutting speed raise during machining of Al–SiC composite.[252] Type of reinforcement also affects the surface quality of the composite. Kumar and Chauhan[253] performed machining on Al–SiC and Al–SiC–graphite composite and found that the HMMCs generates better surface quality compared to the ceramic reinforced MMC.[254] The addition of graphite reinforcement that works as a solid lubricant is accountable for better surface finish and low tool wear in HMMCs.[253]