EFFECT OF HEAT TREATMENT ON (Cr, Fe)7C3/γ-Fe COATINGS IN SITU SYNTHESIZED BY VACUUM ELECTRON BEAM IRRADIATION

(Cr, Fe)7C3/[Formula: see text]-Fe composite layer has been in situ synthesized on a low carbon steel surface by vacuum electron beam VEB irradiation. The synthesized samples were then subdued to different heat treatments to improve their impaired impact toughness. The microstructure, impact toughness and wear resistance of the heat-treated samples were studied by means of optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM), microhardness tester, impact test machine and tribological tester. After heat treatment, the primary and eutectic carbides remained in their original shape and size, and a large number of secondary carbides precipitated in the iron matrix. Since the Widmanstatten ferrite in the heat affected zone (HAZ) transformed to fine ferrite completely, the impact toughness of the heat-treated samples increased significantly. The microhardness of the heat-treated samples decreased slightly due to the decreased chromium content in the iron matrix. The wear resistance of 1000[Formula: see text]C and 900[Formula: see text]C heat-treated samples was almost same with the as-synthesized sample. While the wear resistance of the 800[Formula: see text]C heat-treated one decreased slightly because part of the austenite matrix had transformed to ferrite matrix, which reduced the bonding of carbides particulates.

Download Full-text

In Situ Production of (Fe,Cr)7C3 Particulate Bundles Reinforced Iron Matrix Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.602-604.456 ◽

2012 ◽

Vol 602-604 ◽

pp. 456-459

Author(s):

Jing Lai Tian ◽

Fang Xia Ye ◽

Li Sheng Zhong ◽

Yun Hua Xu

Keyword(s):

Heat Treatment ◽

Wear Resistance ◽

White Cast Iron ◽

Treatment Time ◽

Reference Sample ◽

Chemical Compositions ◽

Matrix Composites ◽

Iron Matrix ◽

Pin On Disc

In-situ production of (Fe,Cr)7C3 particulate bundles -reinforced iron matrix composite was prepared by infiltration casting between Cr wires and white cast iron at 1200°C plus subsequent heat treatment. The composites under different heat treatment times were comparatively characterized by scanning electron microscopy (SEM) and pin-on-disc wear resistance tests. The results show that the area of the particle bundles gradually increases with the heat treatment time increasing, and the chemical compositions change from eutectic to hypoeutectic, the morphologies of the reinforcements present chrysanthemum-shaped, granular and intercrystalline eutectics. Under 5 N loads, the composites appear excellent wear resistance, which is 36 times for the reference sample.

Download Full-text

Infiltration Casting and In Situ Fabrication of (Fe,Cr)7C3 Particulates Bundle – Reinforced Iron Matrix Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.284-286.273 ◽

2011 ◽

Vol 284-286 ◽

pp. 273-276

Author(s):

Li Sheng Zhong ◽

Yun Hua Xu ◽

Xin Cheng Liu ◽

Fang Xia Ye ◽

Jing Lai Tian ◽

...

Keyword(s):

Heat Treatment ◽

Wear Resistance ◽

Cast Iron ◽

Phase Analysis ◽

Matrix Composite ◽

Treatment Process ◽

Heat Treatment Process ◽

Matrix Composites ◽

Iron Matrix

The method of infiltration casting plus heat treatment process employing chromium wires and cast iron applied to in-situ synthesized (Fe,Cr)7C3 particulates bundle reinforced iron matrix composites. The phase analysis, microstructure, microhardness and wear-resistance of composite were observed and measured. The results show that it is possible to fabricate (Fe,Cr)7C3 particulates bundle reinforced iron matrix composite produced by this technology, and a special structure which called particulates bundle was fabricated. (Fe,Cr)7C3 particulates bundle were distributed in the forms of granular, lath-shaped and hexagon-shaped in the particulates bundle. The macrohardness of particulates bundle was 52 HRC, and the relative wear resistance of the composites is 2.3—23 times higher than that of the cast iron.

Download Full-text

Microstructure and Wear Properties of In Situ Production of (Fe,Cr)7C3 Particulate Bundles Reinforced Iron Matrix Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.652-654.64 ◽

2013 ◽

Vol 652-654 ◽

pp. 64-68 ◽

Cited By ~ 1

Author(s):

Jing Lai Tian ◽

Fang Xia Ye ◽

Li Sheng Zhong ◽

Yun Hua Xu

Keyword(s):

Heat Treatment ◽

Wear Resistance ◽

Treatment Time ◽

Heat Treatment Time ◽

Wear Testing ◽

Dry Sliding Wear ◽

Matrix Composites ◽

Wear Properties ◽

Iron Matrix

In-situ production of (Fe,Cr)7C3 particulate bundles-reinforced iron matrix composites were prepared by infiltration casting between Cr wires and white cast iron at 1200°C plus subsequent heat treatment. The composites prepared under different heat treatment time were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), macrohardness test and pin-on-disc wear resistance test. The results show that the composite is mainly consist of (Fe,Cr)7C3 carbides and γ-Fe. The area of the particulate bundles gradually increases with the increase of heat treatment time, the microstructure evolved from eutectic to hypoeutectic, and the morphologies of the reinforcements present chrysanthemum-shaped, granular and intercrystalline eutectics, respectively. The (Fe,Cr)7C3 particulate bundles reinforced composite has high macrohardness and excellent wear resistance under dry sliding wear testing conditons.

Download Full-text

Research on Microstructure and Wear Resistance of (Fe,Cr)7C3/Fe Surface Gradient Composite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1120-1121.559 ◽

2015 ◽

Vol 1120-1121 ◽

pp. 559-563

Author(s):

Chong Wang ◽

Fang Xia Ye ◽

Li Sheng Zhong ◽

Ying Lin Yan ◽

Yu Jun Lai ◽

...

Keyword(s):

Heat Treatment ◽

Wear Resistance ◽

Volume Fraction ◽

Subsurface Layer ◽

Composite Layer ◽

High Volume ◽

Synthesis Process ◽

X Ray Diffraction ◽

Surface Gradient

In this study, the (Fe,Cr)7C3 particles strengthened gradient composite was produced by in situ synthesis process with subsequent heat treatment from gray cast iron (HT300) and high purity chrome plate. The microstructure, phase composition and wear resistance of the composite were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD) and scratch tester. The results showed that the thickness of the gradient layer was about 758 μm after heat treatment at 900 °Cfor 4 h. And it can be divided into three areas depending on microstructure. The outermost layer which was ~60 μm of thickness, was the dense ceramic layer with high volume fraction of (Fe,Cr)7C3 ~90%. No obvious grain boundaries were observed. The subsurface layer was the particles dispersed layer, which was ~525 μm of thickness, with the volume fraction of (Fe,Cr)7C3 decreased to 70%. The lowermost layer was ferrite, with about 173 μm thickness. A good metallurgical bond generated between the composite layer and matrix. The depth and the width of surface scratch increased with the raising loads from 0 to 100 N, and the cracks mainly included micro-crack, tiny dens crack, mixture crack and through-wall crack. The (Fe,Cr)7C3 particles were broken and scraped when the load exceeded 80 N.

Download Full-text

The effect of heat treatment and impact angle on the erosion behavior of nickel-tungsten carbide cold spray coating using response surface methodology

Emergent Materials ◽

10.1007/s42247-021-00274-7 ◽

2021 ◽

Author(s):

Marios Kazasidis ◽

Elisa Verna ◽

Shuo Yin ◽

Rocco Lupoi

Keyword(s):

Heat Treatment ◽

Response Surface Methodology ◽

Mass Loss ◽

Tungsten Carbide ◽

Response Surface ◽

Spray Coating ◽

Impact Angle ◽

Control Factors ◽

Heat Treated ◽

The Impact

AbstractThis study elucidates the performance of cold-sprayed tungsten carbide-nickel coating against solid particle impingement erosion using alumina (corundum) particles. After the coating fabrication, part of the specimens followed two different annealing heat treatment cycles with peak temperatures of 600 °C and 800 °C. The coatings were examined in terms of microstructure in the as-sprayed (AS) and the two heat-treated conditions (HT1, HT2). Subsequently, the erosion tests were carried out using design of experiments with two control factors and two replicate measurements in each case. The effect of the heat treatment on the mass loss of the coatings was investigated at the three levels (AS, HT1, HT2), as well as the impact angle of the erodents (30°, 60°, 90°). Finally, the response surface methodology (RSM) was applied to analyze and optimize the results, building the mathematical models that relate the significant variables and their interactions to the output response (mass loss) for each coating condition. The obtained results demonstrated that erosion minimization was achieved when the coating was heat treated at 600 °C and the angle was 90°.

Download Full-text

The Impact of Heat Treatment on the Behavior of a Hot-Dip Zinc Coating Applied to Steel During Dry Friction

Materials ◽

10.3390/ma14030660 ◽

2021 ◽

Vol 14 (3) ◽

pp. 660

Author(s):

Dariusz Jędrzejczyk ◽

Elżbieta Szatkowska

Keyword(s):

Heat Treatment ◽

Wear Resistance ◽

Friction Coefficient ◽

Dry Friction ◽

Zinc Coating ◽

Pin On Disc ◽

The One ◽

The Impact ◽

Coating Hardness ◽

Anticorrosion Properties

The analyzed topic refers to the wear resistance and friction coefficient changes resulting from heat treatment (HT) of a hot-dip zinc coating deposited on steel. The aim of research was to evaluate the coating behavior during dry friction after HT as a result of microstructure changes and increase the coating hardness. The HT parameters should be determined by taking into consideration, on the one hand, coating wear resistance and, on the other hand, its anticorrosion properties. A hot-dip zinc coating was deposited in industrial conditions (according EN ISO 10684) on disc-shaped samples and the chosen bolts. The achieved results were assessed on the basis of tribological tests (T11 pin-on-disc tester, Schatz®Analyse device, Sindelfingen, Germany), microscopic observations (with the use of optical and scanning microscopy), EDS (point and linear) analysis, and microhardness measurements. It is proved that properly applied HT of a hot-dip zinc coating results in changes in the coating’s microstructure, hardness, friction coefficient, and wear resistance.

Download Full-text

Effect of Cooling Rate on Microstructure and Properties of Heat-Treated Fe3Al Intermetallics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.189-193.3891 ◽

2011 ◽

Vol 189-193 ◽

pp. 3891-3894

Author(s):

Ya Min Li ◽

Hong Jun Liu ◽

Yuan Hao

Keyword(s):

Heat Treatment ◽

Cooling Rate ◽

Lattice Distortion ◽

Annealing Furnace ◽

Microstructure And Properties ◽

Homogenizing Annealing ◽

Heat Treated ◽

Mixed Fracture ◽

Sand Mould ◽

The Impact

The casting Fe3Al intermetallics were solidified in sodium silicate sand mould and permanent mould respectively to get different cooling rates. After heat treatment (1000°С/15 h homogenizing annealing + furnace cooling followed by 600°С/1 h tempering + oil quenching), the microstructure and properties of Fe3Al intermetallics were investigated. The results show that the heat-treated Fe3Al intermetallics at higher cooling rate has finer grained microstructure than lower cooling rate, and the lattice distortion increases due to the higher solid solubility of the elements Cr and B at higher cooling rate. The tensile strength and hardness of the Fe3Al intermetallics at higher cooling rate are slightly higher also. However, the impact power of intermetallics at higher cooling rate is 67.5% higher than that at lower cooling rate, and the impact fracture mode is also transformed from intercrystalline fracture at lower cooling rate to intercrystallin+transcrystalline mixed fracture at higher cooling rate.

Download Full-text

Application of Tailored Heat Treated Blanks under Quasi Series Conditions

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.344.383 ◽

2007 ◽

Vol 344 ◽

pp. 383-390 ◽

Cited By ~ 3

Author(s):

Marion Merklein ◽

Uwe Vogt

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Local Heat ◽

Strength Distribution ◽

Process Window ◽

Short Term ◽

Forming Process ◽

Heat Treated ◽

Set Up ◽

The Impact

Tailored Heat Treated Blanks (THTB) are blanks that exhibit locally different strength specifically optimized for the succeeding forming process. The strength distribution is set by a local, short-term heat treatment modifying the mechanical properties of the material. Hence, THTB allow enhancing forming limits significantly leading to shorter and more robust manufacture process chains. In order to qualify the use of THTB under quasi series conditions, the interdependencies of the blank’s local heat treatment and the entire process chain of the car body manufacture have to be analyzed. In this respect, the impact of a short-term heat treatment on the mechanical properties of AA6181PX, a commonly used aluminum alloy in today’s car bodies, was studied. Also the influence of a short-term heat treatment on the coil lubricant, usually already applied by the material supplier, was given a closer look. Based on these experiments process restrictions for the application of THTB in an industrial automotive environment were derived and a process window for the THTB design was set up. In conclusion, strategies were defined how to enhance the found process boundaries leading to a more robust process window.

Download Full-text