Hair surface quality: Laser scattering as a tool for characterizing the surface condition and deposits from shampoos and conditioners

The study presented investigates the fatigue strength of the (α+β) Ti-6Al-4V-ELI titanium alloy processed by laser cutting with and without mechanical post-processing. The surface quality and possible notch effects as a consequence of non-optimized intermediate cutting parameters are characterized and evaluated. The microstructural changes in the heat-affected zone (HAZ) are documented in detail and compared to samples with a mechanically post-processed (barrel grinding, mechanical polishing) surface condition. The obtained results show a significant increase (≈50%) in fatigue strength due to mechanical post-processing correlating with decreased surface roughness and minimized notch effects when compared to the surface quality of the non-optimized laser cutting. The martensitic α’-phase is detected in the HAZ with the formation of distinctive zones compared to the initial equiaxial α+β microstructure. The HAZ could be removed up to 50% by means of barrel grinding and up to 100% through mechanical polishing. A fracture analysis revealed that the fatigue cracks always initiate on the laser-cut edges in the as-cut surface condition, which could be assigned to an irregular macro and micro-notch relief. However, the typical characteristics of the non-optimized laser cutting process (melting drops and significant higher surface roughness) lead to early fatigue failure. The fatigue cracks solely started from the micro-notches of the surface relief and not from the dross. As a consequence, the fatigue properties are dominated by these notches, which lead to significant scatter, as well as decreased fatigue strength compared to the surface conditions with mechanical finishing and better surface quality. With optimized laser-cutting conditions, HAZ will be minimized, and surface roughness strongly decreased, which will lead to significantly improved fatigue strength.

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Evaluation of the Working Surface of the Grinding Wheel Using Speckle Image Analysis

Volume 1: Processing ◽

10.1115/msec2015-9416 ◽

2015 ◽

Author(s):

Arunachalam Narayanaperumal ◽

Vijayaraghavan Lakshmanan

Keyword(s):

Surface Quality ◽

Surface Condition ◽

Grinding Wheel ◽

Optical Parameters ◽

Wheel Surface ◽

Wheel Wear ◽

Speckle Image ◽

Periodic Monitoring ◽

Grinding Machine

The surface quality of the ground components mainly depends on the surface condition of the grinding wheel. The surface condition of the grinding wheel changes with grinding time due to wheel wear and loading. The excessive wear and loading increases the cutting force and the temperature. This in turn affects the quality of the produced component. Hence periodic monitoring of the grinding wheel surface is essential to avoid the production of the defective components. In this paper, an attempt is made to study the changes in the grinding wheel surface condition using the laser scattered images. The simple speckle imaging arrangement is fabricated and fitted into the grinding machine to capture the images of the grinding wheel after each 100 passes. The fresh wheel expected to scatter more light due to higher roughness and porosity. On the other hand, the completely glazed and worn-out wheel scatters the light less due to smoother surface. Thus, speckle image intensity distribution captures the changes in the grinding wheel surface condition. The optical parameters evaluated from the speckle images clearly indicating the changes in the grinding wheel condition. This method can be utilized to evaluate the grinding wheel condition to improve the surface quality of the component produced.

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Recognition and Control of the Influence Factors on the Surface Defects of Cold Rolled Strip with Emulsion Lubrication

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.456.498 ◽

2013 ◽

Vol 456 ◽

pp. 498-502

Author(s):

Yan Li ◽

Jian Lin Sun

Keyword(s):

Cold Rolling ◽

Surface Quality ◽

Surface Defects ◽

Surface Condition ◽

Influence Factors ◽

Black Spot ◽

Rolling Process ◽

Rolled Strip ◽

Strip Surface ◽

Cold Rolled

In cold rolling, good surface quality should be maintained with the requirement of constant increasing productivity. Oil-in-water (O/W) emulsions are widely used in cold rolled strips due to their good characteristics as lubricants and coolants. The strip surface defect is one of the central quality problems in the rolling process. A poor strip surface quality after cold rolling may have a large impact on the downstream process, like annealing, galvanization and painting. The surface condition could be deteriorated in many forms affected by various factors. However, few reports focused on the effect of the lubricating property of emulsion on the final surface quality. In this paper, the general surface defects of cold rolled strips such as watermark defects, black spot defects, heat scratches and corrosion defects were analyzed by scan electron microscope (SEM) and energy spectrum analysis (EDS) and the morphology and composition of the defects have been researched. The reason of the surface defects generated is analyzed, and the factors which introduce the surface defects during rolling process are presented. Therefore, it has an important significance to identify the features of the surface defects and put forward the solution measures.

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A Mathematical Transform to Analyze Part Surface Quality in Manufacturing

Journal of Manufacturing Science and Engineering ◽

10.1115/1.538904 ◽

1999 ◽

Vol 122 (1) ◽

pp. 273-279 ◽

Cited By ~ 6

Author(s):

Irem Y. Tumer ◽

Kristin L. Wood ◽

Ilene J. Busch-Vishniac

Keyword(s):

Surface Quality ◽

Manufacturing Process ◽

Manufacturing System ◽

Surface Condition ◽

Potential Utility ◽

High Quality ◽

Accurate Design ◽

The Status ◽

Part Surface ◽

Manufacturing Parameters

The status of fault patterns on part surfaces can provide valuable information about the condition of a manufacturing system. Accurate detection of the part surface condition in manufacturing ensures the fault-free manufacturing of high-quality parts, as well as helping in the accurate design/redesign of machine components and manufacturing parameters. To address this problem, we introduce an alternative mathematical transform that has the potential to detect faults in manufacturing machines by decomposing signals into individual components. Specifically, the paper focuses on the decomposition of numerically generated data using the Karhunen-Loe`ve transform to study a variety of signals from manufacturing. The potential utility of the proposed technique is then discussed in the context of understanding a manufacturing process under constant development. [S1087-1357(00)01801-3]

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Effect of Carbon Nanotubes Intensified Coolant on the Grinding Performance of Carburizing and Quenching 12Cr2Ni4A Steel

10.21203/rs.3.rs-515974/v1 ◽

2021 ◽

Author(s):

Gaofeng Zhang ◽

Dejing Luo ◽

Gaocan Wu ◽

Da Liu ◽

Jiakun Wang ◽

...

Keyword(s):

Carbon Nanotubes ◽

Surface Roughness ◽

Surface Quality ◽

Cross Section ◽

Surface Condition ◽

High Heat ◽

High Heat Transfer ◽

Dry Grinding ◽

Heat Transfer Capacity ◽

The Cross

Abstract 12Cr2Ni4A steel is a high-quality alloy structural steel. This article explores the surface/sub-surface condition, surface roughness, and micromorphology of the workpiece surface after grinding 12Cr2Ni4A steel via nanofluid casting to characterize the surface quality and analyzes the burn condition of the workpiece based on the microhardness of the cross-section of the workpiece and the micro-morphology of the subsurface of the workpiece. The test results indicate that the high heat transfer capacity of the carbon nanotube nanofluid can prevent the workpiece from being burned; further, the nanofluid casting type grinding obtains the lowest grinding force and surface roughness compared to the normal and tangential grinding forces. The surface roughness is reduced by 19.2%, 25.0%, and 19.1% at the highest because the nanoparticles (carbon nanotubes) play a “lubricating effect” in the grinding area, and the surface quality of the workpiece is therefore improved. The microhardness of the cross-section of the workpiece indicates that a softened layer appears on the workpiece after dry grinding at normal temperature and on the workpiece after traditional casting grinding. The maximum softening layer thickness for normal temperature dry grinding and traditional casting grinding is ~100 and 40 µm, respectively; no obvious softening layer was observed in nanofluid casting grinding. Tempering burns and secondary quenching burns appear on the subsurface of the workpieces of normal temperature dry grinding and traditional casting grinding. The thicknesses of the affected layers of the tempering and secondary quenching burns are ~98 and 35 µm, respectively; for the nanofluid casting, no obvious burns were observed on the sub-surface of the workpiece ground by type grinding. Thus, this research aims to explore how to minimize grinding burns and propose a new type of nanofluid casting grinding technology.

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Development of a New BCB ELID Lapping Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.154-155.1739 ◽

2010 ◽

Vol 154-155 ◽

pp. 1739-1743

Author(s):

Wei Li ◽

Qian Jun Tian

Keyword(s):

Surface Roughness ◽

Surface Quality ◽

Material Removal Rate ◽

Material Removal ◽

Removal Rate ◽

Surface Condition ◽

Machining Process ◽

Wheel Surface ◽

Abrasive Wheel ◽

Workpiece Surface

In this paper, the mechanism of Electrolysis In-process Dressing (ELID) lapping process using new BCB (bamboo charcoal bonded) abrasive wheel is researched. Some experiments of machining for silicon wafers were carried out for exploring the effect of some machining process parameters on material removal rate and surface roughness. Experiments show that: Material removal rate and machined workpiece surface roughness are increased with increase of the lapping wheel’s rotation speed and processing loading; The machined workpiece surface quality is affected with the lapping wheel surface condition, due to the abrasives are trued by electrolysis dressing in the lapping process, therefore the BCB lapping wheel always keeps better machining condition to obtain excellent machined workpiece surface quality efficiently.

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Internal Surface Quality Enhancement of Selective Laser Melted Inconel 718 by Abrasive Flow Machining

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4047141 ◽

2020 ◽

Vol 142 (10) ◽

Author(s):

Jiang Guo ◽

Chuanping Song ◽

Youzhi Fu ◽

Ka Hing Au ◽

Chun Wai Kum ◽

...

Keyword(s):

Particle Size ◽

Quality Improvement ◽

Surface Quality ◽

Inconel 718 ◽

Surface Condition ◽

Internal Surface ◽

Surface Evolution ◽

Abrasive Flow Machining ◽

Internal Surfaces ◽

Wide Range

Abstract Additive manufacturing (AM) technology enables a new way for fabricating components with complex internal surfaces. Selective laser melting (SLM), being one of the most common AM techniques, is able to fabricate complex geometries with superior material properties. However, due to the poor surface quality, the fabricated internal surfaces cannot meet the specifications for some real applications. To achieve the required internal surface condition, post-polishing process is essential. As one of the most prominent processes for finishing inaccessible surfaces with a wide range of materials, abrasive flow machining (AFM) shows great potential to polish AM internal surfaces. Hence, this paper presents an analytical and experimental study on the internal surface quality improvement of SLM Inconel 718 by AFM, aiming to verify the feasibility of AFM on internal surface quality improvement. The surface evolution process was modeled, and the effects of process parameters on surface and subsurface quality were evaluated. The results show that good surface roughness was obtained at the medium conditions of high viscosity, large particle size, low extrusion pressure, and low temperature. The surface morphology was greatly affected by the medium particle size which showed consistency with the surface evolution model that small abrasive particles are unable to overcome the width and depth of the valleys, resulting in the formation of craters. The partially melt layer was effectively removed, and no subsurface damage was induced.

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