Microstructural Attributes to the Stability of ‘Brass’-Texture During Cold Rolling of AA7010 High Strength Aluminium Alloy

Stainless steels have widespread applications due to their good corrosion resistance, but for certain types of large naval constructions, other requirements are imposed such as high strength and toughness , and modified magnetic characteristics.The magnetic characteristics of a 302 type metastable austenitic stainless steel has been assessed after various cold rolling treatments designed to increase strength by strain inducement of martensite. A grade 817M40 low alloy medium carbon steel was used as a reference material.The metastable austenitic stainless steel after solution treatment possesses a fully austenitic microstructure. However its tensile strength , in the solution treated condition , is low.Cold rolling results in the strain induced transformation to α’- martensite in austenitic matrix and enhances the tensile strength. However , α’-martensite is ferromagnetic , and its introduction to an otherwise fully paramagnetic matrix alters the magnetic response of the material. An example of the mixed martensitic-retained austenitic microstructure obtained after the cold rolling experiment is provided in the SEM micrograph of Figure 1.

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Mechanical clinching and self-pierce riveting for sheet combination of 780-MPa high-strength steel and aluminium alloy A5052 sheets and durability on salt spray test of joints

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-020-06545-7 ◽

2021 ◽

Vol 113 (1-2) ◽

pp. 59-72

Author(s):

Yohei Abe ◽

Ken-ichiro Mori

Keyword(s):

Aluminium Alloy ◽

High Strength Steel ◽

Salt Spray ◽

High Strength ◽

Alloy Sheet ◽

Galvanized Steel ◽

Load Reduction ◽

Minimum Thickness ◽

Steel Sheets ◽

Mechanical Clinching

AbstractTo increase the usage of high-strength steel and aluminium alloy sheets for lightweight automobile body panels, the joinability of sheet combinations including a 780-MPa high-strength steel and an aluminium alloy A5052 sheets by mechanical clinching and self-pierce riveting was investigated for different tool shapes in an experiment. All the sheet combinations except for the two steel sheets by self-pierce riveting, i.e., the two steel sheets, the two aluminium alloy sheets, and the steel-aluminium alloy sheets, were successfully joined by both the joining methods without the gaps among the rivet and the sheets. Then, to show the durability of the joined sheets, the corrosion behaviour and the joint strength of the aged sheets by a salt spray test were measured. The corrosion and the load reduction of the clinched and the riveted two aluminium alloy sheets were little. The corrosion of the clinched two steel sheets without the galvanized layer progressed, and then the load after 1176 h decreased by 85%. In the clinched two galvanized steel sheets, the corrosion progress slowed down by 24%. In the clinched steel and aluminium alloy sheets, the thickness reduction occurred near the minimum thickness of the upper sheet and in the upper surface on the edge of the lower aluminium alloy sheet, whereas the top surface of the upper sheet and the upper surface of the lower sheet were mainly corroded in the riveted joint. The load reduction was caused by the two thickness reductions, i.e., the reduction in the minimum thickness of the upper sheet and the reduction in the flange of the aluminium alloy sheet. Although the load of the clinched steel without the galvanized coating layer and aluminium alloy sheets decreased by about 20%, the use of the galvanized steel sheet brought the decrease by about 11%. It was found that the use of the galvanized steel sheets is effective for the decrease of strength reduction due to corrosion.

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An Evaluation of Quality and Performance of Self-Piercing Riveted High Strength Aluminium Alloy AA6008 for Automotive Applications

10.4271/2010-01-0223 ◽

2010 ◽

Cited By ~ 4

Author(s):

Dezhi Li ◽

Li Han ◽

Martin Thornton ◽

Mike Shergold

Keyword(s):

Aluminium Alloy ◽

High Strength ◽

Automotive Applications ◽

And Performance

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The Study on the Fabrication of Nano-Structured Steel by Cold Rolling and Annealing of Martensite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.1807 ◽

2013 ◽

Vol 634-638 ◽

pp. 1807-1810

Author(s):

Guang Xu ◽

Jing Yang ◽

Tao Xiong ◽

Peng Deng ◽

Long Fei Cao

Keyword(s):

Grain Size ◽

Cold Rolling ◽

High Strength ◽

Total Elongation ◽

Plain Carbon Steel ◽

Mean Grain Size ◽

Cold Rolling And Annealing ◽

The Mean ◽

Martensite Microstructure ◽

Very High

Sub-nano structured steel was obtained by cold rolling and annealing martensite microstructure for a plain carbon steel. The mean grain size is several hundreds nanometer. The steel has very high strength and also good total elongation.

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Cold Rolling and Annealing of Advanced High Strength Steels

Rolling of Advanced High Strength Steels ◽

10.1201/9781315120577-12 ◽

2017 ◽

pp. 482-521

Author(s):

Rosalia Rementeria ◽

Francisca G. Caballero

Keyword(s):

Cold Rolling ◽

High Strength Steels ◽

High Strength ◽

Advanced High Strength Steels ◽

Cold Rolling And Annealing

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Effect of the Stability of Retained Austenite on Elongation in Hot-Rolled High Strength Steels

Tetsu-to-Hagane ◽

10.2355/tetsutohagane1955.82.4_333 ◽

1996 ◽

Vol 82 (4) ◽

pp. 333-337 ◽

Cited By ~ 8

Author(s):

Osamu KAWANO ◽

Jun-ichi WAKITA ◽

Manabu TAKAHASHI

Keyword(s):

Retained Austenite ◽

High Strength Steels ◽

High Strength ◽

The Stability ◽

Hot Rolled

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Study On Setting Method of Flatness Target Curve of SUNDWIG 20-High Mill Considering Target Crown

10.21203/rs.3.rs-818483/v1 ◽

2021 ◽

Author(s):

Jianliang Sun ◽

Mingze Yan ◽

Mingyuan Li ◽

Tongtong Hao

Keyword(s):

Control Theory ◽

Cold Rolling ◽

Hot Rolling ◽

New Method ◽

Discrimination Model ◽

Flatness Control ◽

Simulation Results ◽

The Stability ◽

And Control

Abstract The flatness target curve is important in the flatness control theory. The accuracy of flatness target curve is an important factor to determine the load of flatness control means and flatness quality. Aiming at the defect that crown of each pass after rolling cannot be controlled quantitatively in the traditional target curve formulation of cold rolling, a new method considering the target crown was proposed. Specifically, the target crown of each pass can be set by combining the total proportional crown change in hot rolling field to each pass and the instability discrimination model in cold rolling field. the total proportional crown change of incoming material and finished product is allocated to each pass, and the instability discrimination model is applied to ensure the stability of the plate. The purpose of new method is to control of the crown of each pass quantitatively, so that the flatness and thickness of plate can meet the production requirements. Taking SUNDWIG 20-high mill and typical rolling products as an example, the simulation results show that, on the basis of ensuring the flatness and obtaining the minimum available crown after rolling, the model can make the flatness and crown meet the production requirements at the same time and control the crown of each pass after rolling quantitatively by setting the target crown of each pass.

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Tensile Properties and Damping Capacity of Cold-Rolled Fe-20Mn-12Cr-3Ni-3Si Damping Alloy

Materials ◽

10.3390/ma14205975 ◽

2021 ◽

Vol 14 (20) ◽

pp. 5975

Author(s):

Jae-Hwan Kim ◽

Jong-Min Jung ◽

Hyunbo Shim

Keyword(s):

Tensile Strength ◽

Cold Rolling ◽

Tensile Properties ◽

Volume Fraction ◽

High Strength ◽

Damping Capacity ◽

Austenite Stability ◽

Ε Martensite ◽

Cold Rolled ◽

The Relationship

The tensile properties and damping capacity of cold-rolled Fe–20Mn–12Cr–3Ni–3Si alloys were investigated. The martensitic transformation was identified, including surface relief with a specific orientation and partial intersection. Besides, as the cold rolling degree increased, the volume fraction of ε-martensite increased, whereas α’-martensite started to form at the cold rolling degree of 15% and slightly increased to 6% at the maximum cold rolling degree. This difference may be caused by high austenite stability by adding alloying elements (Mn and Ni). As the cold rolling degree increased, the tensile strength linearly increased, and the elongation decreased due to the fractional increment in the volume of martensite. However, the damping capacity increased until a 30% cold rolling degree was approached, and then decreased. The irregular tendency of the damping capacity was confirmed, depicting that it increased to a specific degree and then decreased as the tensile strength and elongation increased. Concerning the relationship between the tensile properties and the damping capacity, the damping capacity increased and culminated, and then decreased as the tensile properties and elongation increased. The damping capacity in the high-strength area tended to decrease because it is difficult to dissipate vibration energy into thermal energy in alloys with high strength. In the low-strength area, on the other hand, the damping capacity increased as the strength increased since the increased volume fraction of ε-martensite is attributed to the increase in the damping source.

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