CAJ | 학술논문

基于第一性原理密度泛函方法，计算研究Al/θ′共格界面对应变时效参数的能量响应，综合讨论外加单向应变、时效温度以及Cu化学活度对界面形成能的影响作用。结果表明：θ′相的界面能随温度的升高而增大，当温度从298 K增加到498 K时，大尺寸的θ′相界面能(γAl/θ′)增大约2.3%，而小尺寸的富铜θ′相界面能(γAl/θ′(Cu-rich))增大约7.6%；在相同温度和应变下，小尺寸的富铜θ′相界面能总是比大尺寸θ′的相界面能低约10%。在室温下，当应变从0增加到2%时，富铜θ′相界面能最大降低约9.2%；不同的应变方式(压缩或拉伸、垂直或平行界面方向)对各类型θ′相界面能的作用效果有所不同，由此影响到其在基体中的析出方式，这应该是应变时效的主要机制之一。
기우제일성원리밀도범함방법，계산연구Al/θ′공격계면대응변시효삼수적능량향응，종합토론외가단향응변、시효온도이급Cu화학활도대계면형성능적영향작용。결과표명：θ′상적계면능수온도적승고이증대，당온도종298 K증가도498 K시，대척촌적θ′상계면능(γAl/θ′)증대약2.3%，이소척촌적부동θ′상계면능(γAl/θ′(Cu-rich))증대약7.6%；재상동온도화응변하，소척촌적부동θ′상계면능총시비대척촌θ′적상계면능저약10%。재실온하，당응변종0증가도2%시，부동θ′상계면능최대강저약9.2%；불동적응변방식(압축혹랍신、수직혹평행계면방향)대각류형θ′상계면능적작용효과유소불동，유차영향도기재기체중적석출방식，저응해시응변시효적주요궤제지일。
Based on first-principles, the potential effects of coherent Al/θ′interfaces under the response to external strains were calculated, and the effect of the uniaxial strain, aging temperature and Cu activity on the interfacial energies of both stoichiometric and Cu-rich Al/θ′ interfaces energies were investigated. The results show that the interfacial energies θ′phase always increase with temperature increasing, the larger size interface energy (γAl/θ′) and smaller size interface energy (γAl/θ′(Cu-rich) ) increase by about 2.3% and 7.6%, respectively, as the temperature increases from 298 to 498 K. Under the same temperature and strain states,γAl/θ′(Cu-rich) is always lower thanγAl/θ′ by about 10%. For a parallel tensile strain of 2% at room temperature, γAl/θ′(Cu-rich) decreases the most by up to about 9.2%. The different strain signs (compressive or tensile) and directions (parallel or vertical) have different influences on the interface energies, and can affect the orientation preference ofθ' precipitates in the matrix. This may be one major mechanism for stain/stress aging.