Influence of the Zinc Sublayer Method Production and Heat Treatment on the Microhardness of the Composite Ni-Al2O3 Coating Deposited on the 5754 Aluminium Alloy

2014 ◽  
Vol 59 (1) ◽  
pp. 355-358
Author(s):  
M. Karaś ◽  
M. Nowak ◽  
M. Opyrchał ◽  
M. Bigaj ◽  
A. Najder
Keyword(s):  
Heat Treatment ◽  
Aluminium Alloy ◽  
Thermal Shock ◽  
Nickel Coating ◽  
Nickel Sulphate ◽  
Al2o3 Coating ◽  
Nickel Coatings ◽  
Watts Bath ◽  
Before And After ◽  
Zinc Interlayer

Abstract In this study, the effect of zinc interlayer on the adhesion of nickel coatings reinforced with micrometric Al2O3 particles was examined. Nickel coating was applied by electroplating on EN AW - 5754 aluminium alloy using Watts bath at a concentration of 150 g/l of nickel sulphate with the addition of 50 g/l of Al2O3. The influence of zinc intermediate coating deposited in single, double and triple layers on the adhesion of nickel coating to aluminium substrate was also studied. The adhesion was measured by the thermal shock technique in accordance with PN-EN ISO 2819. The microhardness of nickel coating before and after heat treatment was additionally tested. It was observed that the number of zinc interlayers applied does not significantly affect the adhesion of nickel which is determined by thermal shock. No defect that occurs after the test, such as delamination, blistering or peeling of the coating was registered. Microhardness of the nickel coatings depends on the heat treatment and the amount of zinc in the interlayer. For both single and double zinc interlayer, the microhardness of the nickel coating containing Al2O3 particles increased after heat treatment, but decreased when a triple zinc interlayer was applied.

Residual Stress and Stress-Strain Relationship of Electrodeposited Nickel Coatings

2005 ◽  
Vol 9 ◽  
pp. 21-30 ◽  
Author(s):  
Yi Chun Zhou ◽  
Y.P. Jiang ◽  
Y. Pan
Keyword(s):  
Residual Stress ◽  
Laser Beam ◽  
Thermal Shock ◽  
Nickel Coating ◽  
Strain Curve ◽  
Stress Strain ◽  
Nickel Coatings ◽  
Strain Relationship ◽  
Electrodeposited Nickel ◽  
Relationship Of

The uniform nickel coatings on substrate of low carbon steel were prepared by an electrodeposition method. The residual stress in the electrodeposited nickel coating was measured by X-ray diffraction (XRD). It was tensile when the coating was not treated. Laser beam thermal shock was used to modify the mechanical properties of the nickel coating. Laser beam thermal shock could redistribute the residual stress in the nickel coating. The residual stress could be converted from tensile to compressive. A tensile method to determine the stress-strain curve of the coating is proposed where the stress-strain relationship of the substrate without coating was determined for the specimen loaded by an applied tensile force.

Effects of Impregnating and Heat Treatment on the Oxidation and Thermal Shock Properties of Pressureless Sintered SiC/Graphite Composites

2012 ◽  
Vol 724 ◽  
pp. 311-314
Author(s):  
Wan Li Yang ◽  
Zhong Qi Shi ◽  
Zhi Hao Jin ◽  
Guan Jun Qiao
Keyword(s):  
Heat Treatment ◽  
Thermal Shock ◽  
Oxidation Resistance ◽  
Vickers Hardness ◽  
Volume Fraction ◽  
Nitrogen Atmosphere ◽  
Silica Sol ◽  
X Ray Diffraction ◽  
Heat Treated ◽  
Before And After

SiC/0~20% graphite (volume fraction) composites were successfully fabricated by pressureless sintering at 1700 °C for 2 h in nitrogen atmosphere. The impregnating and heat treatment process for the samples with silica sol/phenolic impregnant was carried out at 1450 °C for 2 h in nitrogen atmosphere. The Vickers hardness, oxidation resistance and thermal shock property of the composites before and after treatment were tested, and the microstructure and phase composition were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). The results shown that the Vickers hardness of SiC/20% graphite was increased from 3.35 GPa to 4.90 GPa by heat treatment, and the oxidation resistance and thermal shock property of the heat treated samples were also improved significantly. The SEM and XRD results revealed that the formation of new SiC particles by the reaction of silica sol and phenolic was the main reason for the mechanical properties improvements.

The Precipitation of Si in AlCuSi Thin Films

1973 ◽  
Vol 31 ◽  
pp. 34-35 ◽  
Author(s):  
R. M. Anderson
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Heat Treatment ◽  
Solid Solution ◽  
Integrated Circuit ◽  
Copper Film ◽  
Solution Concentration ◽  
X Ray ◽  
Silicon Thin Films ◽  
Before And After

Aluminum-copper-silicon thin films have been considered as an interconnection metallurgy for integrated circuit applications. Various schemes have been proposed to incorporate small percent-ages of silicon into films that typically contain two to five percent copper. We undertook a study of the total effect of silicon on the aluminum copper film as revealed by transmission electron microscopy, scanning electron microscopy, x-ray diffraction and ion microprobe techniques as a function of the various deposition methods.X-ray investigations noted a change in solid solution concentration as a function of Si content before and after heat-treatment. The amount of solid solution in the Al increased with heat-treatment for films with ≥2% silicon and decreased for films <2% silicon.

Study of fine structure of cold-deformed steel 20 before and after prerecrystallization heat treatment

2015 ◽  
Vol 0 (1) ◽  
Author(s):  
Oleksandr M. Dubovyi ◽  
Oleksandr V. Chechel ◽  
Oleksandr O. Zhdanov
Keyword(s):  
Heat Treatment ◽  
Fine Structure ◽  
Before And After ◽  
Steel 20

Effect of preset interfacial ZrB2 particles on the microstructure and properties of C/C-AlSi composites

2021 ◽  
pp. 002199832110046
Author(s):  
Wei Feng ◽  
Chengwei Tang ◽  
Lei Liu ◽  
Jian Chen ◽  
Yang Zhang ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Thermal Expansion ◽  
Thermal Shock ◽  
Retention Rate ◽  
Pressure Infiltration ◽  
Micro Scale ◽  
Before And After ◽  
Micro Morphology ◽  
Strength Retention ◽  
Fiber Fabric

ZrB2 particles were preset to the C-AlSi interface to improve oxidation resistance of C/C preform and adjust the microstructure of the interpenetrated C/C-AlSi composite prepared through pressure infiltration of eutectic AlSi into a fiber fabric based porous C/C skeleton. Micro-morphology investigations suggested that the AlSi textures were changed from dendritic to petals-like state, and the nano to micro-scale ZrB2 particles were dispersed into AlSi and affected the distribution of Al and Si nearby carbon. Tests demonstrated that C/C-AlSi have slight lower density and thermal expansion coefficient, and higher original compressive strength, while C/C-ZrB2-AlSi composites presented an outstanding strength retention rate after thermal shock. Fracture and micro-morphology indicated that the influence of the preset ZrB2 to the interface of carbon and alloy greatly affected the generation and propagation of cracks, which determined the diverse compression behaviors of the composites before and after thermal shock.

Effect of heat treatment on mechanical properties of forged aluminium alloy AA2219

2021 ◽  
Author(s):  
Mathew Alphonse ◽  
V.K. Bupesh Raja ◽  
M.S. Vivek ◽  
N.V. Sai Deepak Raj ◽  
M. Satya Sai Darshan ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Aluminium Alloy

scholarly journals The Interface Zone of Explosively Welded Titanium/Steel after Short-Term Heat Treatment

2021 ◽  
Author(s):  
Marcin Szmul ◽  
Katarzyna Stan-Glowinska ◽  
Marta Janusz-Skuza ◽  
Agnieszka Bigos ◽  
Andrzej Chudzio ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Intermetallic Phase ◽  
Welding Process ◽  
Carbon Diffusion ◽  
Sharp Interface ◽  
High Plasticity ◽  
Interface Zone ◽  
Before And After ◽  
Wavy Interface ◽  
The Waves

AbstractThis work presents a detailed description of a bonding zone of explosively welded Ti/steel clads subjected to stress relief annealing, applied in order to improve the plasticity of the final product. The typical joint formed by the welding process possesses a characteristic wavy interface with melted regions observed mainly at the crest regions of waves. The interface of Ti/steel clads before and after annealing was previously investigated mostly in respect to the melted regions. Here, a sharp interface between the waves was analyzed in detail. The obtained results indicate that the microstructure of a transition zone of that area is different along the width. After the heat treatment at 600 °C for 1.5 hours, titanium carbide (TiC) together with α-Fe phase forms at the interface in local areas of relatively wide interlayer (~ 1 µm), while for most of the sharp interface, a much thinner zone up to about 400 nm, formed by four sublayers containing intermetallic phase and carbides, is present. This confirms that carbon diffusion induced by applied heat treatment significantly influences the final microstructure of the Ti/steel interface zone. Side bending tests confirmed high plasticity of welds after applied heat treatment; however, the microhardness measurements indicated that the strengthening of the steel in the vicinity of the interface had not been removed completely.

Prediction of suitable heat treatment for H13 tool steels by application of thermal shock fatigue cycle

2021 ◽  
pp. 135065012110118
Author(s):  
Palani Karthikeyan ◽  
Sumit Pramanik
Keyword(s):  
Heat Treatment ◽  
Crack Initiation ◽  
Thermal Shock ◽  
Tool Steel ◽  
Treatment Method ◽  
Industrial Applications ◽  
Tool Steels ◽  
H13 Steel ◽  
H13 Tool Steel ◽  
Cyclic Treatment

In industry, thermally shocked components lead to early failures and unexpected breakdowns during production resulting in huge losses in profit. Thus, the present study investigates the as-received, hardened and hardened and nitrogen treated H13 tool steels subjected to a thermal shock gradient similar to the actual industrial applications. The thermal shock gradients were created by using an in-house-built thermal shock fatigue cyclic treatment machine. The effect of thermal shock fatigue cyclic treatments at 1000 and 2000 thermal shock cycles in hot and molten metal chambers was noticed. All the thermal shock fatigue cyclic-treated samples were analysed by hardness, X-ray diffraction, microscopy and magnetic tests. The interesting changes in hardness, distorted crystal structure and crack initiation were found to be different for differently treated H13 tool steel specimens. The molten aluminium was more prone to stick to the surface of as-received as well as hardened and nitrogen treated steel compared to the hardened H13 steel specimens, which would delay the crack initiation. The wear resistance properties of the hardened H13 steel specimens were found to be higher than as-received and hardened and nitrogen treated H13 steel specimens after thermal shock fatigue cyclic treatment. The loss in magnetic properties was significant for the hardened and hardened and nitrogen treated samples compared to as-received H13 tool steel specimens. Therefore, the present 1000 and 2000 thermal fatigue cycles for 30 s at 670 °C would be worthy to predict the proper heat treatment method to design the parameters as well as the life of die-casting components and to help in the economical production of casting.

Microstructure and Mechanical Properties of Ti-6Al-4V Manufactured by SLM

2015 ◽  
Vol 651-653 ◽  
pp. 677-682 ◽  
Author(s):  
Anatoliy Popovich ◽  
Vadim Sufiiarov ◽  
Evgenii Borisov ◽  
Igor Polozov
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Phase Composition ◽  
Mechanical Behavior ◽  
Ductile Fracture ◽  
Elevated Temperatures ◽  
Initial Material ◽  
Laser Melting ◽  
Microstructure And Mechanical Properties ◽  
Before And After

The article presents results of a study of phase composition and microstructure of initial material and samples obtained by selective laser melting of titanium-based alloy, as well as samples after heat treatment. The effect of heat treatment on microstructure and mechanical properties of specimens was shown. It was studied mechanical behavior of manufactured specimens before and after heat treatment at room and elevated temperatures as well. The heat treatment allows obtaining sufficient mechanical properties of material at room and elevated temperatures such as increase in ductility of material. The fractography of samples showed that they feature ductile fracture with brittle elements.

Modification of Hydrogen Zeolite with CeO2 and its Catalysis Application for Preparing Aspirin

2014 ◽  
Vol 809-810 ◽  
pp. 884-889
Author(s):  
Zhen Tan ◽  
Hui Ying Chen ◽  
Bi Hao Lan ◽  
Xiang Wen Tong ◽  
Xiao Mei Ba
Keyword(s):  
Heat Treatment ◽  
Calcination Temperature ◽  
Catalytic Efficiency ◽  
Optimal Conditions ◽  
Calcination Time ◽  
Zeolite Framework ◽  
High Efficient ◽  
Zeolite Particle ◽  
Before And After ◽  
Impregnation Temperature

Hydrogen zeolite was modified with CeO2 by impregnation - filtration - heat treatment. Hydrogen-zeolite samples before and after modification were characterized by XRD and SEM. The catalytic efficiency of modified hydrogen-zeolite was investigated. Such modification conditions were explored: as the CeO2 percentage, calcination temperature, calcination time, impregnation temperature. The results show that the optimal CeO2 percentage is 0.5%, calcination temperature is 600°C, calcination time is 2h, impregnation temperature is 75°C. The aspirin yield reaches 78.3% under the optimal conditions, compared with that (64.8%) catalyzed by sulfuric acid and that (70.4%) catalyzed by unmodified zeolite. XRD, SEM characterizations show that Ce ions can be doped into the zeolite framework. And the modification makes the zeolite particle size become smaller, which is reduced to 50.5nm from 56.76nm. A high efficient and eco-enviromently catalyst was got by modification.

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