A New Approach for the Prediction of Surface and Subsurface Properties after Grinding

2014 ◽  
Vol 1018 ◽  
pp. 189-196 ◽  
Author(s):  
Stepan Jermolajev ◽  
Ekkard Brinksmeier
Keyword(s):  
Surface Layer ◽  
Contact Time ◽  
Mechanical Load ◽  
X Ray Diffraction ◽  
Workpiece Material ◽  
Workpiece Surface ◽  
New Approach ◽  
Characteristic Values ◽  
Maximum Contact ◽  
Zone Temperature

This paper presents a diagram of maximum contact zone temperatureTmaxversus contact timeΔt, based on the analysis of workpiece surface layer properties after cylindrical grinding experiments. Apart from resulting surface layer properties, process quantities (Tmax, normal and tangential grinding forcesFn,Ft) are investigated with reference to the resulting workpiece surface layer state as well. Ground workpieces are analyzed by performing Barkhausen noise level measurements together with subsequent metallographic and X-ray diffraction investigations. By mapping characteristic valuesTmaxand the contact timeΔtto corresponding surface layer properties, a general analysis of workpiece material response to the thermo-mechanical load during grinding is possible.

scholarly journals Effect of Built-Up Edge Formation on Residual Stresses Induced by Dry Cutting of Normalized Steel

2014 ◽  
Vol 996 ◽  
pp. 603-608
Author(s):  
Johannes Kümmel ◽  
Jens Gibmeier ◽  
Volker Schulze ◽  
Alexander Wanner
Keyword(s):  
Surface Layer ◽  
Metal Cutting ◽  
Cutting Tool ◽  
Cutting Temperature ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Wear Behaviour ◽  
Dry Cutting ◽  
Workpiece Material ◽  
Workpiece Surface

The tool and workpiece surface layer states of the tribosystem uncoated WC-Co cutting tools vs. normalised SAE 1045 workpiece material are studied in detail for a dry metal cutting process. Within the system the cutting parameters (cutting speed, feed rate, cutting depth) determine the wear state of the cutting tool and the resulting surface layer state (residual stress) in the workpiece. As the built-up edge can be used as a possible wear protecting layer [1] the influence of built-up edge and wear behaviour of the cutting tool was examined with respect to the workpiece surface layer state for knowledge based metal cutting processing. Small compressive stresses (-60-80 MPa) are induced in the surface layer, that are nearly homogeneous for the highest built-up edge, which lead to the lowest tool wear in combination with lowest cutting temperature.

scholarly journals THERMAL INFLUENCE ON THE SURFACE INTEGRITY DURING SINGLE-LIP DEEP HOLE DRILLING OF STEEL COMPONENTS

2021 ◽  
Vol 2021 (3) ◽  
pp. 4636-4643
Author(s):  
J. Nickel ◽  
◽  
N. Baak ◽  
P. Volke ◽  
F. Walther ◽  
...  
Keyword(s):  
Surface Integrity ◽  
Force Measurement ◽  
Mechanical Load ◽  
Machining Process ◽  
Hole Drilling ◽  
Workpiece Material ◽  
Workpiece Surface ◽  
Process Measurement ◽  
Color Ratio ◽  
Thermal Influence

The thermomechanical load on the workpiece surface during the machining process strongly influences its surface integrity and the resulting fatigue strength of the components. In single-lip drilling, the measurement of the mechanical load using dynamometers is well established, but the thermal interactions between the tool and the workpiece material in the surface area are difficult to determine with conventional test setups. In this paper, the development and implementation of an in-process measurement of the thermal load on the bore subsurface is presented. The experimental setup includes a two-color ratio pyrometer in combination with thermocouples, which enable temperature measurement on the tool’s cutting edge as well as in the bore subsurface. In combination, a force measurement dynamometer for measuring the occurring force and torque is used. Thus, the influence of different cutting parameter variations on the thermomechanical impact on the bore surface can be evaluated.

Microstructure of Electro-Eroded Cemented Carbide Surfaces

1968 ◽  
Vol 26 ◽  
pp. 284-285
Author(s):  
V. N. Filimonenko ◽  
M. H. Richman ◽  
J. Gurland
Keyword(s):  
Surface Layer ◽  
Cobalt Content ◽  
Cemented Carbides ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
Metallographic Examination ◽  
Standard Procedures ◽  
Face Centered ◽  
Diamond Paste ◽  
Plastic Carbon

The high temperatures and pressures that are found in a spark gap during electrical discharging lead to a sharp phase transition and structural transformation in the surface layer of cemented carbides containing WC and cobalt. By means of X-ray diffraction both W2C and a high-temperature monocarbide of tungsten (face-centered cubic) were detected after electro-erosion. The W2C forms as a result of the peritectic reaction, WC → W2C+C. The existence and amount of the phases depend on both the energy of the electro-spark discharge and the cobalt content. In the case of a low-energy discharge (i.e. C=0.01μF, V = 300v), WC(f.c.c.) is generally formed in the surface layer. However, at high energies, (e.g. C=30μF, V = 300v), W2C is formed at the surface in preference to the monocarbide. The phase transformations in the surface layer are retarded by the presence of larger percentages of cobalt.Metallographic examination of the electro-eroded surfaces of cemented carbides was carried out on samples with 5-30% cobalt content. The specimens were first metallographically polished using diamond paste and standard procedures and then subjected to various electrical discharges on a Servomet spark machining device. The samples were then repolished and etched in a 3% NH4OH electrolyte at -0.5 amp/cm2. Two stage plastic-carbon replicas were then made and shadowed with chromium at 27°.

scholarly journals Exploiting superspace to clarify vacancy and Al/Si ordering in mullite

IUCrJ ◽  
2018 ◽  
Vol 5 (4) ◽  
pp. 497-509 ◽  
Author(s):  
Paul Benjamin Klar ◽  
Iñigo Etxebarria ◽  
Gotzon Madariaga
Keyword(s):  
Density Functional ◽  
X Ray Diffraction ◽  
Intrinsic Structure ◽  
Functional Theory ◽  
New Approach ◽  
X Ray ◽  
Vacancy Ordering ◽  
Harmonic Modulation ◽  
First Time

Synchrotron single-crystal X-ray diffraction has revealed diffuse scattering alongside sharp satellite reflections for different samples of mullite (Al4+2xSi2−2xO10−x). Structural models have been developed in (3+1)-dimensional superspace that account for vacancy ordering and Al/Si ordering based on harmonic modulation functions. A constraint scheme is presented which explains the crystal-chemical relationships between the split sites of the average structure. The modulation amplitudes of the refinements differ significantly by a factor of ∼3, which is explained in terms of different degrees of ordering,i.e.vacancies follow the same ordering principle in all samples but to different extents. A new approach is applied for the first time to determine Al/Si ordering by combining density functional theory with the modulated volumes of the tetrahedra. The presence of Si–Si diclusters indicates that the mineral classification of mullite needs to be reviewed. A description of the crystal structure of mullite must consider both the chemical composition and the degree of ordering. This is of particular importance for applications such as advanced ceramics, because the physical properties depend on the intrinsic structure of mullite.

scholarly journals Controlled Growth of CdS Nanostep Structured Arrays to Improve Photoelectrochemical Performance

2020 ◽  
Vol 8 ◽  
Author(s):  
Jiangang Jiang ◽  
He Wang ◽  
Hongchang An ◽  
Guangyuan Du
Keyword(s):  
Tin Oxide ◽  
Energy Conversion Efficiency ◽  
Photoelectrochemical Cells ◽  
X Ray Diffraction ◽  
Reaction Parameters ◽  
Photoelectrochemical Performance ◽  
New Approach ◽  
Phase Purity ◽  
X Ray ◽  
Straight Rod

CdS nanostep-structured arrays were grown on F-doped tin oxide-coated glasses using a two-step hydrothermal method. The CdS arrays consisted of a straight rod acting as backbone and a nanostep-structured morphology on the surface. The morphology of the samples can be tuned by varying the reaction parameters. The phase purity, morphology, and structure of the CdS nanostep-structured arrays were characterized by X-ray diffraction and field emission scanning electron microscopy. The light and photoelectrochemical properties of the samples were estimated by a UV-Vis absorption spectrum and photoelectrochemical cells. The experimental results confirmed that the special nanostep structure is crucial for the remarkable enhancement of the photoelectrochemical performance. Compared with CdS rod arrays, the CdS nanostep-structured arrays showed increased absorption ability and dramatically improved photocurrent and energy conversion efficiency. This work may provide a new approach for improving the properties of photoelectrodes in the future.

scholarly journals PEMANFAATAN LIMBAH KULIT BUAH PISANG KEPOK (Musa paradisiaca) SEBAGAI BIOSORBEN ZAT WARNA RHODAMIN B

KOVALEN ◽  
2019 ◽  
Vol 5 (3) ◽  
pp. 308-314
Author(s):  
Musafira Musafira ◽  
Nurfitrah M Adam ◽  
Dwi Juli Puspitasari
Keyword(s):  
Adsorption Capacity ◽  
Rhodamine B ◽  
Contact Time ◽  
Banana Peel ◽  
Musa Paradisiaca ◽  
Randomized Design ◽  
Rhodamine B Dye ◽  
Completely Randomized Design ◽  
Maximum Contact ◽  
Rhodamin B

The investigation about the utilization of Banana peel (Musa paradisiaca) as biosorbent Rhodamine B dye has been done The purpose of this study was to determine the maximum contact time and to determine the adsorption capacity of kepok banana peel. Completely randomized design (CRD) was used in this research with two variables (the contact time and Rhodamine B concentration. Both variables were done in five levels i.e 10, 30, 60, 90, and 120 min and 2, 4, 6, 8 and 10 ppm respectively. The result showed that the maximum concentration of banana peel in adsorbing Rhodamine B was 6 ppm with 120 of contact time, and Rhodamine B adsorption capacity was  4.55mg/g. Keywords: Banana peel, Rhodamine B, biosorbent

The investigation of disturbed surface layer structure by the external photoeffect under X-ray diffraction conditions

1982 ◽  
Vol 71 (2) ◽  
pp. 603-610 ◽  
Author(s):  
V. G. Kohn ◽  
M. V. Kovalchuk ◽  
E. M. Imamov ◽  
B. G. Zakharov ◽  
E. F. Lobanovioh
Keyword(s):  
Surface Layer ◽  
Layer Structure ◽  
X Ray Diffraction ◽  
X Ray

scholarly journals Evaluation of modified montmorillonite with di-cationic surfactants as efficient and environmentally friendly adsorbents for arsenic removal from contaminated water

2017 ◽  
Vol 18 (2) ◽  
pp. 460-472 ◽  
Author(s):  
E. Shokri ◽  
R. Yegani ◽  
B. Pourabbas ◽  
B. Ghofrani
Keyword(s):  
Contact Time ◽  
Arsenic Removal ◽  
Environmentally Friendly ◽  
Contaminated Water ◽  
X Ray Diffraction ◽  
Solution Ph ◽  
Modified Montmorillonite ◽  
Adsorption Capacities ◽  
Modified Adsorbents ◽  
Adsorption Desorption

Abstract In this work, montmorillonite (Mt) was modified by environmentally friendly arginine (Arg) and lysine (Lys) amino acids with di-cationic groups for arsenic removal from contaminated water. The modified Mts were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, zeta potential and thermal analysis. The adsorption of As(V) onto modified Mts as a function of initial As(V) concentration, contact time and solution pH was investigated. The removal efficiency was increased with increasing the As(V) concentration and contact time; however, it was decreased with increasing solution pH. The maximum As(V) adsorption capacities of Mt-Arg and Mt-Lys were 11.5 and 11 mg/g, respectively, which were five times larger than pristine Mt. The high adsorption capacity makes them promising candidates for arsenic removal from contaminated water. The regeneration studies were carried out up to 10 cycles for both modified Mts. The obtained results confirmed that the modified adsorbents could also be effectively used for As(V) removal from water for multiple adsorption – desorption cycles.

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