Study on Electric Contact Heating for Nodular Cast Iron 600-3

2012 ◽  
Vol 152-154 ◽  
pp. 316-321 ◽  
Author(s):  
Xiao Ben Qi ◽  
Shi Gen Zhu
Keyword(s):  
Cast Iron ◽  
Nodular Cast Iron ◽  
Processing Parameters ◽  
Optical Microscope ◽  
Work Piece ◽  
Electric Contact ◽  
Hardened Zone ◽  
Melted Zone ◽  
Contact Heating ◽  
Modified Layer

The method of electric contact heating for nodular cast iron was based on the application of the contact resistance heating between the electrode and work piece to change the characteristics of the surface. The effects of processing parameters on the width and depth of modified layer were analyzed, and among the experimental factors, the electric current had the largest effect than the others. Optical microscope was used to describe the microstructure transformation and identify the phases in the modified layer. Results showed that a cementite-martensite microstructure in the melted zone and a martensite-ledeburite-ferrite microstructure with graphite nodules in the hardened zone have been observed; especially two typical hardened shells around graphite are achieved in the hardened zone, which are ledebruite-martensite shell and single martensite shell around graphite. The effects of the changed microstructures were additionally verified by microhardness measurements in the modified zone. The microhardness of the nodular cast iron was found to be significantly increased after electric contact heating.

Formation of the Cast Iron Coatings Plasma-Sprayed at Different Substrate Temperatures

2010 ◽  
Vol 44-47 ◽  
pp. 2144-2147
Author(s):  
Ya Zhe Xing ◽  
Chao Ping Jiang ◽  
Hong Chen ◽  
Jian Min Hao
Keyword(s):  
Cast Iron ◽  
Substrate Temperature ◽  
Phase Structure ◽  
Processing Parameters ◽  
Optical Microscope ◽  
Atmospheric Plasma ◽  
Cross Sectional ◽  
The Cross ◽  
Plasma Sprayed ◽  
Iron Coatings

In this work, three cast iron coatings were produced by atmospheric plasma spraying. During spraying, the surface temperature of three coatings (substrate temperature) was controlled to be averagely 50oC, 180oC and 240oC by changing the processing parameters. X-ray diffraction (XRD) was employed to analyze the phase structure of the starting powder and the coatings. The results showed that the powder was mainly composed of (Fe,Cr)7C3 and martensite and both the spraying processing and the substrate temperature exerted no influence on coating phase structure. An optical microscope (OM) was used to characterize the microstructure of the cross-section and surface of the coatings. It was found that the cross sectional hardness increased with the increase of the substrate temperature due to the improvement in interlamellar bonding.

scholarly journals Melt Stirring of Nodular Cast Iron

2018 ◽  
Vol 925 ◽  
pp. 125-132
Author(s):  
Fareed Ashraf Khan ◽  
Hasse Fredriksson
Keyword(s):  
Cast Iron ◽  
Nodular Cast Iron ◽  
Optical Microscope ◽  
Area Fraction ◽  
Distribution Area ◽  
Graphite Phase ◽  
Nodule Count ◽  
Nucleation Sites ◽  
Count Distribution ◽  
Scanning Electron

In this work the effects of stirring/vigorous shearing on matrix and graphite phase in nodular cast iron melt during solidification were studied. Several experiments were conducted for different cooling and stirring times. Samples were prepared and examinations of the microstructure were conducted and compared using Leica Optical Microscope and Scanning Electron Microscope (SEM). In addition, a chemical analysis of the graphite precipitate was performed using EDX equipment mounted on SEM. Oxidation of the melt and formation of oxide nuclei during stirring were observed and analysed. The influence of melt shearing on the structure, nodule count, distribution, area fraction and on overall graphite precipitation was observed and examined with the help of respective computer programs and soft wares. Stirring resulted in increasing the nucleation sites for graphite precipitation thereby increasing the nodule count and area fraction of carbide and transforming the structure from pearlitic matrix to ferritic matrix.

scholarly journals Remanufacturing of nodular cast iron crankshaft with plasma cladding

2018 ◽  
Vol 10 (6) ◽  
pp. 168781401877985 ◽  
Author(s):  
Jinxia Liu ◽  
Chao Ma ◽  
Luda Yu ◽  
Yu Wang ◽  
Zhiyuan Jiao
Keyword(s):  
Cast Iron ◽  
Nodular Cast Iron ◽  
Processing Parameters ◽  
Cladding Layer ◽  
Remaining Service Life ◽  
Working Surface ◽  
Plasma Cladding ◽  
Wide Range ◽  
Cladding Layers

Remanufacturing technology has a wide range of applications in the repair of scrapped parts with a certain remaining service life. In this work, a scrapped crankshaft fabricated from nodular cast iron that had failed from working surface wear was remanufactured via a plasma cladding process. Taking into account the wear amount on the working surface and the characteristics of nodular cast iron, in this article, cladding layer parameters were designed and two types cladding powders, Fe-based and Ni-based, were prepared, respectively, to perform the cladding experiment. After examining different process parameters, relatively smooth cladding layers were obtained using four powders. The cladding experiment results showed that the powder No. 3 exhibited superior qualities when combined with proper processing parameters. When applying powder No. 3 to the main journal of crankshaft, a higher quality of cladding layer was achieved.

scholarly journals Microstructure, Hardness and Corrosion Resistance of Surface Modified Ni - Hard 4 Cast Iron with Nitrogen Using Gas Tungsten Arc

2019 ◽  
Vol 8 (2) ◽  
pp. 5360-5365
Keyword(s):  
Cast Iron ◽  
Corrosion Rate ◽  
Protective Layer ◽  
Optical Microscope ◽  
Nacl Solution ◽  
Gas Tungsten Arc ◽  
Depth Direction ◽  
Polarization Test ◽  
Modified Layer ◽  
Surface Modified

The change in microstructure, hardness and corrosion rate of Ni-Hard 4 cast iron were studied after surface modification with Nitrogen mixed the Argon shielding environment. The microstructure of the modified layer was grains with the presence of nitrogen, observed under the optical microscope. An average of 1.37wt% of Nitrogen was observed in the modified layer during EDAX analysis. The presence of Nitrogen in the modified layer has formed FeN, Ni3N and Cr2N phases. The formation of nitride phases were confirmed during XRD spectral analysis. The hardness of the modified layer was taken along the depth direction. The hardness of the modified layer was improved from 578HV of the substrate to 1735HV of the modified layer. The electrochemical polarization test was conducted at a 3.5wt. % saline (NaCl) solution in both the substrate and the modified layer. The modified layer forms a protective layer over the surface and reduced the corrosion rate than the substrate

Analysis of electro- and thermophysical processes occurring during electrocontact baking of flour products.

2020 ◽  
Vol 29 (11) ◽  
pp. 50-55
Author(s):  
V.I. Maklyukov ◽  
◽  
E.O. Gerasimova ◽  
N. V. Labutina ◽  
E.N. Rogozkin ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Theoretical Calculation ◽  
Heat Balance ◽  
Electric Contact ◽  
Wheat Dough ◽  
Baking Process ◽  
Free Moisture ◽  
Contact Heating ◽  
The Heat Balance

The article considers the results of research conducted during electric contact heating of rye-wheat dough pieces. It is established that the electrical conductivity of the crumb dough does not depend on the total humidity of the material, but mainly on the amount of free moisture. Using the current and temperature graphs, you can imagine how free moisture changes during the baking process and the influence of the thermophysical and colloidal process on the change in the value of free moisture. Experimentally determined the amount of heat that is spent on baking 1 kg of bread. The accuracy of the theoretical calculation of this parameter in the heat balance of the baking chamber is confirmed.

Effective properties of nodular cast-iron: A multi-scale computational approach

2014 ◽  
Vol 82 ◽  
pp. 378-390 ◽  
Author(s):  
F.D. Carazo ◽  
S.M. Giusti ◽  
A.D. Boccardo ◽  
L.A. Godoy
Keyword(s):  
Cast Iron ◽  
Effective Properties ◽  
Nodular Cast Iron ◽  
Computational Approach ◽  
Multi Scale

The Effect of Parameters of Laser Processing on the Morphology of Glaze Cladding

2012 ◽  
Vol 586 ◽  
pp. 265-268 ◽  
Author(s):  
Ji Wei Fan ◽  
Zhi Qiang Jiao ◽  
Xiao Peng Li ◽  
Hui Jun Zhao ◽  
Zhen Guo Zhang ◽  
...  
Keyword(s):  
Output Power ◽  
Processing Speed ◽  
Laser Processing ◽  
Ceramic Materials ◽  
Processing Parameters ◽  
Laser Technique ◽  
Experimental Conditions ◽  
Melted Zone

Laser processing ceramic materials is a new application of laser technique. This paper presents the study of laser processing parameters of glaze cladding. It found out that the parameters of laser processing affected the morphology of glaze cladding significantly. Within the experimental conditions, rise of output power or drop of processing speed can increase the depth of melted zone and the width of glaze cladding, vice versa.

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