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the origin of aging effect in ferroelectrics because these materials possess different defects and exhibit various aging behavior. The reverse transition temperature in lead titanate doped with lanthanum... physical properties in ferroelectrics significantly. The abnormal increase of the reverse transition temperature was discussed in terms of diffusion of point defects during aging. Dielectric performance......
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steps were investigated. Various procedure and the parameters for melt purifying, finishing rolling temperature, split aging parameters, and water cooling capacity during casting and hot rolling were... influencing the quality of C194 alloy sheet and strip. Key words: C194 alloy; finishing rolling temperature; split aging 1 Introduction Copper alloys are major materials for lead frame usage......
) and yield strength (YS) increase first and then decrease. While the UTS and YS are significantly decreased with the increase of aging temperature. For example, under the condition of aging temperature... temperature at 170 °C with aging time from 2 h to 24 h, the UTS and YS decrease by 19.2% and 29.6%, respectively. Fig. 1 Effect of two-step aging on tensile strength of AA7085: Figure 2 depicts the results......
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and 85.5% IACS, respectively. Increasing aging temperature accelerated aging precipitation. The time for attaining peak hardness was postponed, the precipitates were finer (2-4 nm), and the interparticle...Aging characteristic of Cu-0.6Cr-0.15Zr-0.05Mg-0.02Si alloy containing trace rare earth yttriumYU Fangxin, CHENG Jianyi, and AO Xuewen School of Materials Science and Engineering, Nanchang University......
Characterization of γ′ precipitates in a nickel base superalloy quenching from aging temperature at different ratesLI Hongyu, SONG Xiping, WANG Yanli, and CHEN Guoliang State Key Lab for Advanced... from 1050°C at different rates were investigated using field emission scanning electron microscope(FESEM).When quenched from 1050°C, the size of primary aging γ′ precipitates has a small increase......
and temperature chamber. A cylinder of dry and clean compressed air was provided by a pressure regulator with air pressure. The standard aging procedure of 100 ℃, 2.1 MPa and 20 h for the PAV was utilized... 3.2.1 Effects on G* Fig.2 shows the curves of G* vs temperature for the pristine and OMMT modified bitumen after TFOT. Bitumen thermal-oxidative aging dramatically decreases the content of oily......
℃ is delayed, which results in its slower age strengthening and over-aging behavior than the alloy aged at 175℃. Meanwhile, aging temperature of 160℃ causes more uniform distribution and finer size of T1, resulting in its better strengthening effect. As aging time and aging temperature are increased, the size of T1 at grain boundaries and the width of PFZ along grain boundaries are increased, leading......
is 72.8 % higher than that under DS condition. Key words: Nb-Ti-Si based ultrahigh temperature alloy; homogenizing treatment; aging treatment; microstructural evolution; microhardness 1 Introduction... Microstructure and microhardness of directionally solidified and heat-treated Nb-Ti-Si based ultrahigh temperature alloy GUO Hai-sheng, GUO Xi-ping State Key Laboratory of Solidification......
