Analysis of Strain Hardening Behaviour of Cast Aluminium Alloy 354 Subjected to Artificial Ageing at Various Temperatures

2013 ◽  
Vol 856 ◽  
pp. 231-235 ◽  
Author(s):  
Aditya Eswar ◽  
Arnav Gupta ◽  
G. Dinesh Babu ◽  
M. Nageswara Rao
Keyword(s):  
Heat Treatment ◽  
Aluminium Alloy ◽  
Strain Hardening ◽  
Automotive Industry ◽  
Mechanical Behaviour ◽  
Artificial Ageing ◽  
Cast Aluminium ◽  
Heat Treated ◽  
Lower Strain ◽  
Wide Scale

Automotive industry makes wide scale use of cast aluminium alloy 354 in the production of crucial components, such as compressor wheels for turbochargers. The compressor wheels undergo T61 heat treatment, involving artificial ageing at 188°C. This study focuses on the possible improvement of the mechanical behaviour of the components by subjecting them to modified heat treatments involving usage of lower artificial ageing temperatures (160, 171 and 177°C). A comparative analysis of tensile properties and strain hardening behaviour has been carried out with different artificial ageing temperatures. Results showed that the heat treatment routinely employed by the industry (aged at 188°C) leads to overageing, thereby resulting in relatively inferior mechanical properties and lower strain hardening rates as compared to the samples heat treated at lower artificial ageing temperatures. It is concluded that lowering of the artificial ageing temperature can lead to a superior state of components with respect to mechanical behaviour.

scholarly journals Study on Fatigue Life of Heat-treated Aluminium alloy coated with Castor oil.

2018 ◽  
Vol 172 ◽  
pp. 03004
Author(s):  
A. Sivasubramanian ◽  
T.S. Kirubasankar ◽  
S. Vinoth kumar
Keyword(s):  
Heat Treatment ◽  
Fatigue Life ◽  
Aluminium Alloy ◽  
Castor Oil ◽  
Cyclic Load ◽  
Heat Treated ◽  
Al 7075 ◽  
Number Of Cycles ◽  
Uncoated Specimen ◽  
Scanning Electron

This paper involves the study of fatigue life of coated aluminium alloy Al 7075-T651 that is heat-treated under 100oC soaked in castor oil for three days. The specimen after heat treatment is subjected to fatigue test using rotary bending machine for number of cycles to fail under cyclic load of 15kgf, 25Kgf, and 50kgf.The life of the specimen is found and compared with uncoated specimen and improved life in number of cycle is noticed. The crack propagation and its type is analysed using scanning electron microscope for knowing the point of fracture and its initiation to failure.

Industrial Heat Treatment of R-HPDC A356 Automotive Brake Callipers

2012 ◽  
Vol 192-193 ◽  
pp. 533-538 ◽  
Author(s):  
Levy Chauke ◽  
Heinrich Möller ◽  
Ulyate Andries Curle ◽  
Gonasagren Govender
Keyword(s):  
Heat Treatment ◽  
Tensile Properties ◽  
Automotive Industry ◽  
Laboratory Scale ◽  
Heat Treated ◽  
Die Cast ◽  
Eutectic Si ◽  
Hardness Increase ◽  
Cast Condition ◽  
Automotive Brake

Heat treatment of rheo-high pressure die cast (R-HPDC) A356 brake callipers has produced good mechanical properties on the laboratory scale. An industrial heat treatment is required to evaluate the applicability and conformance of the R-HPDC A356 brake callipers to the automotive industry. This research studied A356 brake callipers heat treated on the industrial scale with particular emphasis on the resulting microstructure, hardness and tensile properties. The eutectic Si-particle spheroidisation after solution heat treatment was achieved and observed with optical microscopy. A hardness increase from 64 to 100 Vickers was achieved from the as-cast condition to the industrially heat treated T6 condition. The heat treatment caused no significant variation in hardness and tensile properties from brake callipers within the same batch or from different batches. The yield and ultimate strengths of the industrial heat treated brake callipers were lower compared to the laboratory scale heat treatment properties, while the ductility increased, mainly due to quenching effects. Even though the industrial heat treated A356 brake callipers resulted in yield and ultimate tensile strengths lower than those achieved on a laboratory scale, they still exceeded the minimum specifications for gravity die cast A356 brake callipers.

The Effect of Heat Treatment on Fatigue and Mechanical Properties of 6061 Aluminium Alloy

2014 ◽  
Vol 699 ◽  
pp. 227-232
Author(s):  
Nurulhilmi Zaiedah Nasir ◽  
Mohd Ahadlin Mohd Daud ◽  
Mohd Zulkefli Selamat ◽  
Ahmad Rivai ◽  
Sivakumar Dhar Malingam
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Impact Strength ◽  
Aluminium Alloy ◽  
Aging Treatment ◽  
Hardness Measurement ◽  
Hardness Tester ◽  
Quenching Media ◽  
Heat Treated ◽  
6061 Aluminium Alloy

This paper investigated the effect of heat treatment on mechanical properties and microstructure of 6061 aluminium alloy. The aluminium alloys were examined in the heat treated conditions, using different quenching media, water and oil. The alloy was solution heat treated at temperature of 529oC for one, three and five hour respectively. Aging treatment was carried out at temperature of 160oC which is assumed to be the best temperature for ageing process. Hardness measurement was carried out using a Brinell Hardness Tester Machine. The results shows hardness and impact strength are inversely proportional to each other, as the hardness of 6061 aluminium alloy decreases and impact strength increases.

Microstructure and Mechanical Propertiesof Ti/Cu-Cr/S20C and Ti/Cu-Ag/S20C Clad Composites

2013 ◽  
Vol 376 ◽  
pp. 153-157 ◽  
Author(s):  
Jong Su Ha ◽  
Sun Ig Hong
Keyword(s):  
Heat Treatment ◽  
High Pressure ◽  
Strain Hardening ◽  
Intermetallic Compounds ◽  
Mechanical Performance ◽  
High Strength ◽  
Strengthening Mechanism ◽  
Reaction Products ◽  
Heat Treated ◽  
Strength And Ductility

In this study Cu-Ag or Cu-Cr layer was sandwiched by Ti and Fe plates and the three layers of Ti/Cu-8Ag/S20C were clad by High Pressure Torsioning(HPT). The effect of post-HPT heat treatment on the interfacial reaction products and the mechanical performance in Ti/Cu-Ag/S20C and Ti/Cu-Cr/S20C clad material were studied. Cu4Ti3 and Cu4Ti Intremetallic compound layers were observed at the Ti/Cu-Ag and Ti/Cu-Cr interfaces in the clad heat-treated at 500°C where as no intermetallic compounds were observed at the Cu-Ag/S20C and Cu-Cr/S20C interfaces. The strength of as-HPTed Ti/Cu-8Ag/S20C is much higher than that of Ti/Cu-1Cr/S20C. The strengthening mechanism of Cu-Ag deformed severely is the interface and strain hardening in which dislocations are deposited at the Cu/Ag interfaces and can contribute to the strengthening of the clad composite just after HPT processing, rendering the high strength just after processing. In both clad composites, the strength and ductility increased after heat treatment at 350°C, which are likely caused by the enhanced bonding at the interfaces.

Investigation on the Strain Behaviour of a Precipitation-Hardenable Aluminium Alloy through a Temperature Gradient Based Heat Treatment

2015 ◽  
Vol 639 ◽  
pp. 361-368 ◽  
Author(s):  
Gabriella di Michele ◽  
Pasquale Guglielmi ◽  
Gianfranco Palumbo ◽  
Donato Sorgente
Keyword(s):  
Heat Treatment ◽  
Temperature Gradient ◽  
Aluminium Alloy ◽  
Room Temperature ◽  
Tensile Tests ◽  
Gauge Length ◽  
Image Correlation ◽  
Experimental Campaign ◽  
Strain Behaviour ◽  
Heat Treated

In this work the strain behaviour of the heat-treated 6xxx series aluminium alloy AC170PX is investigated by a not conventional approach. Thanks to the low density combined with good mechanical properties, this aluminium alloy is often adopted for automotive applications. Despite these advantages, its formability at room temperature is low. In order to overcome this limit, a distribution of the material properties can be achieved by a local heat treatment (Tailored Heat Treated Blanks). In this context, to evaluate the effects of those parameters mainly affecting the precipitation hardening (aging temperature and aging time), a first experimental campaign was conducted using conventional furnace heat treatment in different conditions . Tensile tests were run with the aim of determining the flow and the aging curves of the heat treated specimens. Starting from these results, a not uniform heat treatment was designed using a Gleeble physical simulator Heat treatments based on a temperature gradient along the sample were performed. Then, tensile tests of the so heated specimens were carried out at room temperature. Through a digital image correlation system both the distribution and the evolution of the strain along the gauge length of the specimen were analysed in order to obtain the hardening/softening working conditions related to a specific heating cycle. These results were validated by the comparison with the data obtained from the first experimental campaign.

Strain Hardening Behaviour of Hipped and Non-Hipped Castings of Aluminium Alloy 354 Subjected to Two-Step Ageing Treatments

2014 ◽  
Vol 906 ◽  
pp. 249-253
Author(s):  
Arnav Gupta ◽  
Aditya Eswar ◽  
G. Dinesh Babu ◽  
M. Nageswara Rao
Keyword(s):  
Mechanical Properties ◽  
Aluminium Alloy ◽  
Strain Hardening ◽  
Ageing Time ◽  
Single Step ◽  
Second Step ◽  
Light Weight ◽  
Cast Aluminium ◽  
Treatment Analysis ◽  
Strain Hardening Rate

Cast aluminium alloys are being employed increasingly in the automotive sector due to their light weight and excellent castability. This paper focuses on the strain hardening behaviour of Hipped and non-Hipped components of cast aluminium alloy 354 subjected to two-step ageing, as opposed to the routinely carried out single-step ageing. First step ageing (at 100°C) was carried out for 2 h and 5 h; ageing time at second step (at 170°C) was 1, 2 and 5 h. Mechanical properties and strain hardening behaviour were evaluated for different variants of two-step ageing treatment. Analysis of the results shows that the Hipped components have higher hardening capacity and generally higher strain hardening rate compared to the non-Hipped ones. Some of the two-step ageing treatments give mechanical properties comparable to the conventional T61 treatment, but with significantly higher strain hardening rate.

scholarly journals Mechanical Behaviour of Stamped Aluminium Alloy Components by Means of Response Surfaces

Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1838 ◽  
Author(s):  
Isidoro Iván Cuesta ◽  
Pavel Michel Almaguer-Zaldivar ◽  
Jesús Manuel Alegre
Keyword(s):  
Mechanical Properties ◽  
Aluminium Alloy ◽  
Automotive Industry ◽  
Mechanical Behaviour ◽  
Response Surfaces ◽  
Engineering Strain ◽  
Response Surface Technique ◽  
Prediction Of Mechanical Properties ◽  
High Plastic ◽  
Surface Technique

In the automotive industry, the use of stamped aluminium alloy components has become a very common occurrence. For the appropriate design of these components, it is necessary to know how the manufacturing process affects the material properties. In the first place, high plastic strains ( ε p ) can be generated during the stamping process, which can result in a change in the residual stress and mechanical properties in the plastically deformed areas. Furthermore, if a last coat of paint that is usually subjected to a thermal cycle, characterized by temperature ( T ) and exposure time ( t ), is applied, it can also influence mechanical behaviour. Consequently, this paper studies how both processes affect the mechanical behaviour of an aluminium alloy of the 5000 series, commonly used in these types of components. In particular, the mechanical properties such as the yield stress at 0.2% ( σ 0.2 ), the ultimate tensile strength ( s u t ) and the engineering strain at break ( e f ) have been analysed. To achieve this, a response surface technique, based on the design of experiments, has been used. The response surfaces obtained allow for the prediction of mechanical properties σ 0.2 , s u t and e f for any combination of values of t , T and ε p .

scholarly journals Influence of Ca, Sb and heat treatment on AlSi9CuMnNi alloy in frame of their properties from view of machining

2018 ◽  
Vol 244 ◽  
pp. 02003 ◽  
Author(s):  
Nataša Náprstková ◽  
Pavel Kraus ◽  
Jan Sviantek ◽  
Tuong Nguyen Van
Keyword(s):  
Heat Treatment ◽  
Tool Wear ◽  
Aluminium Alloy ◽  
Aluminium Alloys ◽  
Mechanical Engineering ◽  
Metal Alloys ◽  
Heat Treated ◽  
Cutting Inserts

Treatment of metal alloys is one of the ways to affect the quality and properties of the material At the Faculty of Mechanical Engineering of the Jan Evangelista Purkyně University in Ústí nad Labem, one part of the research consists of searching for the influence of various modifying and inoculating elements on selected aluminium alloys. One of the alloys undergoing the present research is the hardening aluminium alloy AlSi9CuMnNi. The article describes one from these experiments, than AlSi9CuMnNi alloy was modified with various amounts of calcium (0.05, 0.1 and 0.15 wt. % Ca) and 0.2 wt. % Sb. The alloy without modification and with 0.2 wt. % Sb was heat-treated, too. In the experiment were made three castings for each type of alloy. Experimental samples were evaluated form view of final hardness, were machined, too and there were analysed tool wear of using cutting inserts and final ship from machining (turning). Presented experiments are part of the extensive research undertaken at FME at JEPU in Ústí nad Labem.

Precipitation Behaviour and Mechanical Properties during Short-Term Heat Treatment for Tailor Heat Treated Profiles (THTP) of Aluminium Alloy 6060 T4

2016 ◽  
Vol 877 ◽  
pp. 400-406 ◽  
Author(s):  
Hannes Fröck ◽  
Matthias Graser ◽  
Benjamin Milkereit ◽  
Michael Reich ◽  
Michael Lechner ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Aluminium Alloy ◽  
Heat Treatments ◽  
Maximum Temperature ◽  
Short Term ◽  
Scanning Calorimetry ◽  
Heat Treated ◽  
Precipitation Behaviour ◽  
Dissolution And Precipitation

Precipitation hardening aluminium alloys are widely used for automotive applications. To enhance the application of aluminium profiles, improved formability is needed. Tailor Heat Treated Profiles (THTP) with locally different material properties attempt to increase formability e.g. in bending processes. Tailoring of local properties is obtained by a local short-term heat treatment, dissolving the initial precipitate state (retrogression) and still allowing subsequent ageing. In the present study, the dissolution and precipitation behaviour of the aluminium alloy EN AW-6060 T4 was investigated during heating with differential scanning calorimetry (DSC). Heating curves from 20 to 600 °C with heating rates of 0.01 up to 5 K/s were recorded. Interrupted heat treatments with different maximum temperatures were performed in a deformation dilatometer. Immediately afterwards, tensile tests were carried out at room temperature. The course of the recorded mechanical properties as a function of the maximum temperature is discussed with regard to the dissolution and precipitation behaviour during heating. Finally, the aging behaviour of the investigated alloy was recorded after different typical short-term heat treatments and is discussed with reference to the DSC‐curves. The correlation of the microstructure and the mechanical properties enables the derivation of optimal parameters for the development of THTP through a local softening.

scholarly journals Effect of Strain Hardening on Precipitation Kinetics in ATI 718Plus

2017 ◽  
Vol 907 ◽  
pp. 167-172
Author(s):  
Bilal Hassan ◽  
Yann Jansen ◽  
Sebastien Nouveau ◽  
Jonathan Corney
Keyword(s):  
Heat Treatment ◽  
Grain Boundaries ◽  
Strain Hardening ◽  
Inconel 718 ◽  
Important Process ◽  
Compression Tests ◽  
Precipitation Kinetics ◽  
Phase Precipitation ◽  
Heat Treated ◽  
Δ Phase

ATI 718Plus components are manufactured by forging a wrought billet in stages to obtain the desired geometry and microstructure. Parts are then heat treated to optimized proportions of γ’ and η phases. η phase is a plate-like phase that precipitates on the grain boundaries of ATI 718Plus, similar to δ phase in Inconel 718. However, the complete kinetic behaviour of η phase precipitation during forging and heat treatment is still not fully understood. This paper investigates the effects of strain hardening on η phase precipitation kinetics in ATI 718Plus. This is achieved through the use of isothermal hot compression tests and heat treatment. Strain hardening was found to affect the η precipitation kinetics considerably. The results reported are a contribution to a fuller understanding of this important process

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