AI 中文总结
研究超短脉冲激光烧蚀建模中Ti和Ti-6Al-4V的电子输运性质，采用第一性原理计算，得出元素Ti和Ti-6Al-4V的相关参数，通过双温度模型模拟发现输运模型函数形式对预测精度比元素与合金区分更重要。
AI 中文摘要
超短脉冲激光烧蚀的预测建模需要从电子结构得出的与温度相关的材料参数，即电子热导率、电子-声子耦合和热容量。这些参数在元素金属中有详细记录，但合金方面记录稀少，重要的钛合金Ti-6Al-4V仍用元素钛值建模。我们从第一性原理计算hcp Ti和Ti-6Al-4V的电子输运，采用Kubo-Greenwood形式主义等。计算出的元素Ti的电阻率与独立计算和实验相符。在电子-声子非平衡下，Ti的电子热导率先饱和后下降，Ti-6Al-4V则低很多。在双温度模型模拟中，合金和元素参数集产生的峰值晶格温度差异小，用低温Drude极限代替第一性原理热导率会使峰值晶格温度变化大，表明输运模型函数形式对预测精度更重要。
英文摘要
Predictive modeling of ultrashort-pulse laser ablation requires temperature-dependent material parameters derived from the electronic structure, namely the electronic thermal conductivity, electron--phonon coupling, and heat capacity. These parameters are well documented for elemental metals but remain sparsely documented for alloys, apart from application-relevant exceptions such as stainless steels. The technologically important titanium alloy Ti-6Al-4V is a prominent example, which is still modeled using elemental-titanium values. We compute the electronic transport of hcp Ti and Ti-6Al-4V from first principles, using the Kubo--Greenwood formalism within the Korringa--Kohn--Rostoker coherent-potential-approximation framework, treating chemical and thermal disorder on equal footing. For elemental Ti, the calculated electrical resistivity agrees with independent \textsc{abinit} electron--phonon calculations and experiment, and also reproduces the high-temperature saturation near the Mott--Ioffe--Regel limit. Under electron--phonon nonequilibrium, the electronic thermal conductivity saturates and then decreases with electronic temperature, reaching a maximum of about \SI{2.97}{\kilo\watt\per\metre\per\kelvin} in Ti but only \SI{0.47}{\kilo\watt\per\metre\per\kelvin} in Ti-6Al-4V, a factor of 6.4 lower. In two-temperature-model simulations the alloy and elemental parameter sets yield peak lattice temperatures differing by only about 1.4\%, consistent with reported experimental ablation thresholds that differ by about 3\%, well within their measurement uncertainties. Replacing the first-principles thermal conductivity with the low-temperature Drude limit shifts the peak lattice temperature by up to 19\%, showing that the functional form of the transport model is even more important than the elemental vs alloy distinction for predictive accuracy.
