scholarly journals TAILORING SURFACE MORPHOLOGY AND TOPOGRAPHY OF SHOT-PEENED Ti6Al4V VIA GRIT BLASTING

2021 ◽  
Vol 55 (5) ◽  
Author(s):  
Yasemin Yıldıran Avcu ◽  
Okan Yetik ◽  
Mert Guney ◽  
Tamer Sınmazçelik ◽  
Egemen Avcu
Keyword(s):  
Surface Roughness ◽  
Quantitative Analysis ◽  
Surface Morphology ◽  
Surface Properties ◽  
Shot Peening ◽  
Wear Mechanisms ◽  
Surface Modifications ◽  
Grit Blasting ◽  
Embedded Particles ◽  
Modified Surface

The present study aims to reveal the effectiveness of grit blasting when modifying the surface properties of a Ti6Al4V alloy deteriorated due to shot peening. Ti6Al4V samples shot-peened under different parameters were grit-blasted (at impingement angles of 30° and 90°, blasting pressures of 1.5 bar and 3 bar). Grit blasting proved to be an effective way of tailoring the surface topography as the surface roughness of shot-peened samples (approx. 10 µm) declined to approx. 2 µm. The surface modifications mainly occurred via micro-ploughing and micro-cutting wear mechanisms, indicating that grit blasting at 30° was more favourable than at 90° for modifying the deteriorated surface properties after shot peening. Shot-peened samples behaved similarly to mirror-polished unpeened samples during grit blasting, showing that the modified surface and subsurface properties obtained via shot peening have an insignificant effect on grit blasting of the alloy. A quantitative analysis of the area covering the embedded particles on the surface of the alloy due to grit blasting showed that the area almost doubled when the alloy was grit blasted at 90° compared to 30°, highlighting an excessive amount of embedding, which would be critical when surface decontamination is important.

Characterization on Surface Properties of Ti–6Al–4V After Multiple Shot Peening Treatments

2016 ◽  
Vol 138 (4) ◽  
Author(s):  
Lechun Xie ◽  
Yan Wen ◽  
Liqiang Wang ◽  
Chuanhai Jiang ◽  
Vincent Ji
Keyword(s):  
Surface Roughness ◽  
Stress Distribution ◽  
Surface Properties ◽  
Shot Peening ◽  
Diffraction Method ◽  
Domain Size ◽  
Treatment Method ◽  
X Ray Diffraction ◽  
Obvious Effect ◽  
Surface Residual Stresses

As an important surface treatment method, shot peening (SP) can improve the surface properties effectively. In this work, after multiple SP treatments, the uniformity of the residual stress distribution and the domain size distribution on the surface of Ti–6Al–4 V have been investigated via an X-ray diffraction method. Compared with traditional SP treatments, the multiple SP can increase the surface residual stresses and make the stress distribution more uniform. In terms of the domain size, the multiple SP treatments mainly influence its uniform distribution, and there is no obvious effect to the values, which is due to the saturation status of SP process. In addition, the effects of multiple SP on the surface roughness and hardness have been studied. The results show that the multiple SP can reduce the surface roughness and increase the hardness in a certain extent comparing with the effect of traditional SP, which are ascribed to the smaller shot balls and the more homogeneous deformation during the process of multiple SP. Therefore, an appropriate multiple SP can improve the surface properties of Ti–6Al–4 V effectively.

scholarly journals Surface Properties of Ultrasonic Vibration-Assisted ELID Grinding ZTA Ceramics

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 636
Author(s):  
Zongxia Fu ◽  
Fan Chen ◽  
Wenbo Bie ◽  
Bo Zhao ◽  
Xiaobo Wang
Keyword(s):  
Surface Roughness ◽  
Surface Morphology ◽  
Surface Properties ◽  
Ultrasonic Vibration ◽  
Material Removal ◽  
Surface Residual Stress ◽  
Machined Surface ◽  
Elid Grinding ◽  
Stress Surface ◽  
Surface Performance

This study aimed to explore the evolution of surface properties of nanocomposite ceramics during ultrasonic vibration-assisted electrolytic in-process dressing (UVA-ELID) grinding. First, the trajectory of the grain was analyzed, and the motion was simulated using MATLAB to demonstrate the mechanism of UVA-ELID grinding. The critical grinding depth was also calculated under the effect of ultrasonic vibration. Then, the conventional ELID (C-ELID) and UVA-ELID grinding were compared. The surface properties, including surface residual stress, surface microstructure, surface roughness, and surface morphology, were used to evaluate the effectiveness and feasibility of UVA-ELID grinding. Whether it was conventional C-ELID or UVA-ELID grinding, the residual compressive stress was introduced into the machined surface, while the former was lower than the latter. The microstructure of the UVA-ELID grinding was evenly distributed, and the ductility removal occurred during material removal. The surface roughness of Ra and Rz was reduced by 14.5% and 20.6%, respectively, during the UVA-ELID grinding. The surface morphology was dramatically changed with the help of ultrasonic vibration. In a word, for nanocomposite ceramic, the UVA-ELID grinding can significantly improve surface performance and achieve a better machining effect.

scholarly journals Ultrasonic dispersion method used in glass polishing experiment

2021 ◽  
Vol 13 (4) ◽  
pp. 168781402110118
Author(s):  
Zenan Chu ◽  
Tao Wang ◽  
Qiang He ◽  
Kai Zhao
Keyword(s):  
Surface Roughness ◽  
Rare Earth ◽  
Surface Morphology ◽  
Ultrasonic Method ◽  
Average Surface Roughness ◽  
Polishing Process ◽  
Ultrasonic Dispersion ◽  
Processing Efficiency ◽  
Average Surface ◽  
Evaluation Indexes

To solve the problems of low processing efficiency and poor glass surface quality when using rare earth polishing powder to grind super-hard K9 glass. The potential, phase structure, surface morphology, and particle size distribution of the nano-rare earth polishing powder were characterized. Compare the evaluation indexes such as polishing efficiency, surface morphology, and contact angle after the polishing process is changed. The results of the comparative study show that the average surface roughness of the glass after heating ultrasonic polishing process is 0.9064 nm, the polishing rate reaches 0.748 μm/min, the average surface roughness of the glass without heating ultrasonic polishing process is 1.3175 nm, and the polishing rate reaches 0.586 μm/min, the ultrasonic assisted polishing process is superior to the conventional polishing process. The heating ultrasonic method provides experimental basis for precise and rapid processing.

scholarly journals Effect of Optical and Morphological Control of Single-Structured LEC Device

Micromachines ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 843
Author(s):  
Woo Jin Jeong ◽  
Jong Ik Lee ◽  
Hee Jung Kwak ◽  
Jae Min Jeon ◽  
Dong Yeol Shin ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Surface Roughness ◽  
Surface Properties ◽  
High Efficiency ◽  
High Surface ◽  
Reduction Rate ◽  
Operating Characteristics ◽  
Emission Layer ◽  
Light Emitting ◽  
Stable Operating

We investigated the performance of single-structured light-emitting electrochemical cell (LEC) devices with Ru(bpy)3(PF6)2 polymer composite as an emission layer by controlling thickness and heat treatment. When the thickness was smaller than 120–150 nm, the device performance decreased because of the low optical properties and non-dense surface properties. On the other hand, when the thickness was over than 150 nm, the device had too high surface roughness, resulting in high-efficiency roll-off and poor device stability. With 150 nm thickness, the absorbance increased, and the surface roughness was low and dense, resulting in increased device characteristics and better stability. The heat treatment effect further improved the surface properties, thus improving the device characteristics. In particular, the external quantum efficiency (EQE) reduction rate was shallow at 100 °C, which indicates that the LEC device has stable operating characteristics. The LEC device exhibited a maximum luminance of 3532 cd/m2 and an EQE of 1.14% under 150 nm thickness and 100 °C heat treatment.

Surface integrity of quenched steel 1045 machined by CBN grinding wheel and SiC grinding wheel

2017 ◽  
Vol 8 (2) ◽  
pp. 179-187 ◽  
Author(s):  
Kankan Ji ◽  
Xingquan Zhang ◽  
Shubao Yang ◽  
Liping Shi ◽  
Shiyi Wang ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Surface Morphology ◽  
Compressive Stress ◽  
Surface Integrity ◽  
Grinding Wheel ◽  
Micro Hardness ◽  
Content Type ◽  
Quenched Steel ◽  
Cut Depth ◽  
Cbn Grinding Wheel

Purpose The purpose of this paper is to evaluate surface integrity of quenched steel 1045 ground drily by the brazed cubic boron nitride (CBN) grinding wheel and the black SiC wheel, respectively. Surface integrity, including surface roughness, sub-surface hardness, residual stresses and surface morphology, was investigated in detail, and the surface quality of samples ground by two grinding wheels was compared. Design/methodology/approach In the present work, surface integrity of quenched steel 1045 machined by the CBN grinding wheel and the SiC wheel was investigated systematically. All the specimens were machined with a single pass in the down-cutting mode of dry condition. Surface morphology of the ground specimen was observed by using OLYMPUS BX51M optical microscopy. Surface roughness of seven points was measured by using a surface roughness tester at a cut-off length of 1.8 mm and the measurement traces were perpendicular to the grinding direction. Sub-surface micro-hardness was measured by using HVS-1000 digital micro-hardness tester after the cross-section surface was polished. The residual stress was tested by using X-350A X-ray stress analyzer. Findings When the cut depth is increased from 0.01 to 0.07 mm, the steel surface machined by the CBN wheel remains clear grinding mark, lower roughness, higher micro-hardness and higher magnitude of compressive stress and fine microstructure, while the surface machined by the SiC grinding wheel becomes worse with increasing of cut depth. The value of micro-hardness decreases, and the surface roughness increases, and the surface compressive stress turns into tensile stress. Some micro-cracks and voids occur when the sample is processed by the SiC grinding wheel with cut depth 0.07 mm. Originality/value In this paper, the specimens of quenched steel 1045 were machined by the CBN grinding wheel and the SiC wheel with various cutting depths. The processing quality resulted from the CBN grinding wheel is better than that resulted from the SiC grinding wheel.

Investigation on Surface Grinding of Ti-6Al-4V Using Minimum Quantity Lubrication

2012 ◽  
Vol 500 ◽  
pp. 308-313 ◽  
Author(s):  
Guo Qiang Guo ◽  
Zhi Qiang Liu ◽  
Xiao Hu Zheng ◽  
Ming Chen
Keyword(s):  
Surface Roughness ◽  
Plastic Deformation ◽  
Surface Morphology ◽  
Specific Energy ◽  
Minimum Quantity Lubrication ◽  
Grinding Force ◽  
Dry Grinding ◽  
Surface Damages ◽  
Side Flow ◽  
Mql System

This paper investigates the effects of MQL system on the grinding performance of Ti-6Al-4V using SiC abrasive, the evaluation of the performance consisted of analyzing the grinding force, surface roughness and surface morphology. The experiment result indicated that the favorable lubricating effect of MQL oil makes it has the lowest value of grinding force, specific energy and force raito. MQL has better surface finish than dry grinding and fluid grinding has the lowest value of surface roughness under different grinding depth. Surface damages such as: side flow, plastic deformation, redeposition are present in dry and fluid grinding. As grinding depth increased, the damages become much more severe. But in MQL condition, it gives better surface integrity than dry and fluid grinding.

scholarly journals Failure Analysis of Rheocast Cylinder Head Covers of Hypereutectic Al–Si Alloys

2020 ◽  
Author(s):  
Jian Feng
Keyword(s):  
Heat Treatment ◽  
Surface Morphology ◽  
Service Time ◽  
Shot Peening ◽  
High Frequency ◽  
Cylinder Head ◽  
Die Casting ◽  
Fatigue Properties ◽  
Homogeneous Distribution ◽  
Engine Components

AbstractThe purpose of the present study is to determine the cause of failures of semisolid rheocast cylinder head covers of hypereutectic modified LM30 alloys. The covers, manufactured by rheocasting, a process that consists of the incorporation and homogeneous distribution of the reinforcements in semisolid metal (SSM) before die casting, were shot-peened after heat treatment to increase the fatigue resistance. However, these engine components failed during operation after a short service time. The major flaws were located by radiography. The microstructure was controlled by metallography. Significant interactions between shot peening and surface/subsurface contaminants were identified by surface morphology and fractography. The fatigue properties of hypereutectic alloys were investigated by a high-frequency vibrophore. It was identified that the failure was related to the cleanliness of SSM as well as the rheocasting process. Recommendations were given to prevent the recurrence of similar failures.

Surface properties of composite resins with and without fluorides for bracket bonding / Propriedades de superfície de resinas compostas com e sem fluoretos para colagem de suportes

2021 ◽  
Vol 7 (7) ◽  
pp. 67267-67276
Author(s):  
Emillyn Jones Greijal Dias Holanda ◽  
José Guilherme Neves ◽  
Milton Santamaria-Jr ◽  
Silvia Amélia Scudeler Vedovello ◽  
Ana Rosa Costa ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Surface Properties ◽  
Color Change ◽  
Composite Resins ◽  
Hardness Tester ◽  
Significant Difference ◽  
Post Test ◽  
Roughness Analysis ◽  
Diamond Paste ◽  
Penetration Time

The aim of this study was to evaluate the surface properties of orthodontic resins with and without fluoride. Forty disks, measuring 2 mm thick by 6 mm in diameter, were made of 4 bracket-bonding composite resins (n=10): Transbond Plus Color Change-3M/Unitek (TPCC); Transbond XT- 3M/Unitek (TXT), Orthocem -FGM (OC); Orthocem UV Trace-FGM (OCUV). The discs were photoactivated for 40 seconds with irradiance of 450 mW/cm2 and manually polished in sequence by silicon carbide sandpapers with 1200 and 2000 grain size and finished with diamond paste and felt disc. The surface microhardness analysis was performed using a Shimadzu Micro Hardness Tester HMV-2,000 (Shimadzu Corporation, Kyoto, Japan) with a load of 50 gF and a 5 second penetration time. Surface roughness readings were taken using a Surf Corder Roughness Meter (SE 1700- Kosaka, Lisboa-Portugal). For data analysis, ANOVA (one-way) was used, followed by Tukey's post-test (?=0.05). The microhardness results showed a difference (p?0.05) in the means of the orthodontic resins between TPCC and TXT with the other groups. After the surface roughness analysis, the averages showed that TPCC resin showed higher roughness compared to OC and OCUV (p?0.05), and there was no statistical difference with TXT. It was concluded that statistically the composite resins with fluoride showed significant difference regarding hardness and roughness.

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