A differential scanning calorimetric study of precipitation in Cu2Be

Structural evolution during non-isothermal ageing of a dilute Al–Cu alloy by dilatometric analysis

“…The main precipitation peak decreases and shifts to higher temperatures with the increase of heating rate. The first effect of the heating rate can be explained by the decrease of the precipitated Cu atoms amount because of its increased solid solubility at the increased precipitation temperatures when using higher heating rate [31,32]. However the second effect is explained by the diffusive nature of the precipitation reactions.…”

Microstructure, mechanical properties and aging behaviour of nanocrystalline copper–beryllium alloy

“…For the CG case, six peaks are shown and labelled A to F. The onset temperatures corresponding to all of the thermal events are listed in Table 3. They can be separated into two groups, namely the first temperature interval of 100 o C to 290 o C and the second from 290 o C to 480 o C. According to previous investigations at the same heating rate [24], these peaks can be identified as follows. Peak "A" is associated with short range atomic motions probably resulting from the fast annihilation of quenched-in vacancies; "B" is related to coherent Guinier-Preston (GP) zones lying in {100} fcc Cu planes; "C" is related to the γ '' metastable phase with a monoclinic structure; "D" is attributed to discontinuous precipitation leading to the nucleation and growth of the stable γ phase directly from the supersaturated solid solution; "E" is associated with the transformation of GP zones or " precipitates into the metastable bcc γ ' phase and "F" is attributed to the transformation of γ '' or γ ' precipitates into the stable bcc γ phase.…”

“…This precipitation sequence can be significantly affected by other alloying elements. Thus addition of Co as an alloying element may prevent nucleation of  phase [24] while addition of Zn leads to skipping metastable " phase [25]. On the other hand, aging behavior of Cu -Be alloys also dependent on the exact aging conditions.…”

“…For example, an increase in the heating rate promotes the direct nucleation of the stable  phase. A complex differential scanning calorimetry study [24] of Cu -2 wt.% Be alloy showed than low and medium heating rates (up to 30 o C/min) lead to simultaneous discontinuous and continuous precipitation processes, while an increase of the heating rate promotes the direct continuous precipitation of the stable  phase. The complicated influence of continuous precipitation on discontinuous precipitation was revealed in [26] and seems to be controlled by the cell volume fraction driven by aging temperature ranges.…”

Effect of Heating Ratesand Zn-Addition on the Thermal Properties Ofpb–snalloy.

“…The first effect of the heating rate can be explained by the decrease of the precipitated Zn atoms amount because of its increased solid 23 solubility at the increased precipitation temperatures when using higher heating rate [19,20]. However the second effect is explained by the diffusive nature of the precipitation reactions.…”