Download or read book The Influence of Quenching and Aging on Fracture Toughness of the Al Zn Mg Cu Alloy 7449 written by J. Robinson and published by . This book was released on 2014 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: This investigation characterises the fracture toughness of the very high strength Aluminium alloy 7449. This Al-Zn-Mg-Cu alloy is heat treatable and relies on rapid quenching from the solution heat treatment temperature to promote subsequent artificial aging. While the influence of quench paths on strength is well understood and can be predicted using techniques like quench factor analysis, the influence of quench rate on fracture toughness is more challenging. The rate of quenching can influence the fracture toughness through complex precipitation reactions occurring during cooling. The precipitate locations dictate the magnitude of the detrimental effect on the fracture toughness. In this investigation, the fracture toughness of 7449 in two product forms was measured using compact tension specimens cut from forged blocks and rolled plate. These plane strain (KIC) results were also augmented with Charpy impact tests. Various quench conditions were investigated, including water at three different temperatures and poly oxyethylene glycol (PAG) in two concentrations. The influence of standard and novel aging procedures including retrogression and reaging was also determined. The combinations of strength and toughness have been related to the prevailing microstructural condition. Fracture toughness magnitudes were found to vary most significantly with rapidity of cooling from the solution treatment temperature, with the subsequent aging treatments having a much smaller effect.

Download or read book Quench Rate and Aging Effects in Aluminum zinc magnesium copper Aluminum Alloys written by Donald Scott MacKenzie and published by . This book was released on 2000 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Magnesium on the Microstructure Hardness and Tensile Properties of Zinc Alloys Containing 25 to 40 Percent Aluminum written by L. A. Neumeier and published by . This book was released on 1971 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stress Corrosion Cracking of Al Zn Mg Cu Alloys written by Steven P. Knight and published by . This book was released on 2008 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Chapter Formability and Performance of Al Zn Mg Cu Alloys with Different Initial Tempers in Creep Aging Process written by Heng Li and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The initial temper may directly affect the deformation behavior and material performance in creep age forming (CAF) process. Five heat treatment states are selected as the initial tempers for CAF, namely, solution, peak-aging (T6), over-aging (T73), retrogression and re-solution. The formability and performance of an Al-Zn-Mg-Cu alloy with the above initial tempers in creep aging process are investigated via using creep and stress relaxation aging tests, mechanical property tests, corrosion resistance tests and microstructure analysis. The differences of formability are attributed to the inhibitions of different distributed matrix precipitates (MPts) on the dislocation movement, namely, the more coarsening the MPts is, the easier the dislocation movement. During creep aging process, the mechanical properties are improved for the solution, retrogression and re-solution tempers with fine MPts, but reduced for the T6 and T73 tempers due to coarsening of MPts. Since the distribution of grain boundary precipitates (GBPs) becomes discontinuous, the corrosion resistances of the creep aged specimens are enhanced for all initial tempers. Taking both mechanical properties and corrosion resistances into account, the re-solution temper may be a preferable choice to achieve high performance of the components beyond the precise shape in CAF.

Download or read book Formability and Performance of Al Zn Mg Cu Alloys with Different Initial Tempers in Creep Aging Process written by Heng Li and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The initial temper may directly affect the deformation behavior and material performance in creep age forming (CAF) process. Five heat treatment states are selected as the initial tempers for CAF, namely, solution, peak-aging (T6), over-aging (T73), retrogression and re-solution. The formability and performance of an Al-Zn-Mg-Cu alloy with the above initial tempers in creep aging process are investigated via using creep and stress relaxation aging tests, mechanical property tests, corrosion resistance tests and microstructure analysis. The differences of formability are attributed to the inhibitions of different distributed matrix precipitates (MPts) on the dislocation movement, namely, the more coarsening the MPts is, the easier the dislocation movement. During creep aging process, the mechanical properties are improved for the solution, retrogression and re-solution tempers with fine MPts, but reduced for the T6 and T73 tempers due to coarsening of MPts. Since the distribution of grain boundary precipitates (GBPs) becomes discontinuous, the corrosion resistances of the creep aged specimens are enhanced for all initial tempers. Taking both mechanical properties and corrosion resistances into account, the re-solution temper may be a preferable choice to achieve high performance of the components beyond the precise shape in CAF.

Download or read book The Mechanisms of Dispersion Strengthening and Fracture in Al based XD tm Alloys Part 1 written by and published by . This book was released on 1990 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: The influence of reinforcement size, volume fraction, and matrix deformation behavior on room and elevated temperature strength; the fracture toughness; and the fatigue crack growth rate of metal matrix composites of Al-4(pct)Cu-1.5(pct)Mg with TiB2 were examined. The influence of reinforcement volume fraction was also examined for pure aluminum with TiB2. Higher TiB2 volume fractions increased the tensile yield strength at both room and elevated temperatures, and reduced the elongation to fracture. Tensile tests also indicate that small particles provided a greater increase in strength for a given volume fraction than larger particles, whereas elongation to fracture appeared to be insensitive to reinforcement size. Interparticle spacing appears to be the factor that controls the strength of these alloys, with the exact nature of the dependence relying on the nature of dislocation slip in the matrix (planar vs. diffuse). The isothermal aging response of the precipitation strengthened Al-4(pct)Cu-1.5(pct)Mg alloys was not accelerated by the presence of TiB2. Cold work prior to artificial aging created additional geometrically necessary dislocations which serve as heterogeneous nucleation sites leading to accelerated aging, a finer precipitate size, and an increase in the strength of the alloy.

Download or read book Microstructure and Fracture Toughness of an Al Zn Mg Alloy written by Thomas Michael Banks and published by . This book was released on 1970 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effect of Strain Aging on the Fracture Toughness of Steel written by and published by . This book was released on 1968 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fracture Toughness and Microstructure of a Thick Al Zn Mg Extrusion written by I. G. Crouch and published by . This book was released on 1978 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effect of Strain Aging on the Fracture Toughness of Steel written by Yun Chung and published by . This book was released on 1968 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Two Step Aging Process on Microstructure and Fracture Toughness of 7085 Aluminum Alloy written by and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development of High strength Al Zn Mg Cu Alloys with Reduced Quench sensitivity written by H. A. Holl and published by . This book was released on 1968 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Aging on Fracture Toughness written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effect of Quenching Rate on Aging Response and Mechanical Properties of Al 7wt Si 0 3Wt Mg Casting Alloy written by Stiliana Raynova and published by . This book was released on 2002 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Microalloying and Heat Treatment on the Structure and Properties of a New Super High Strength Al Zn Mg Cu Alloy written by Yi-Lei Wu and published by . This book was released on 1997 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Precipitation in Al Zn Mg Cu Alloys Modified With Sc and Zr During Aging Preprint written by and published by . This book was released on 2006 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper was developed under a SBIR contract. The effect of Sc additions on precipitation strengthening in AI-Zn-Mg-Cu alloys was studied after natural and artificial aging. Phase analysis was performed using transmission electron microscopy and computer simulations. Microhardness of the alloys was studied after different steps of aging and the strengthening mechanisms were discussed. It was found that Sc does not affect the kinetics of aging at room temperature, which is controlled by formation and growth of GPI zones. Sc also does not affect the kinetics of aging at 150C, which is controlled by formation and growth of eta' and eta particles. However, the additions of Sc accelerate the aging process at l20C within a period of time of formation and growth of GPII zones. It is concluded that the presence of Sc accelerates formation and growth of GPII zones in the Al-Zn-Mg-Cu alloys during artificial aging.