Ultrafast　optical　excitation　induced　transient　modification　on　the　energy-band　structures　in　tungsten,　which　resulted　in　the　expansion　and　shift　toward　the　Fermi-level　of　d-band.　This　process　led　to　enhanced　interband　transitions　at　reduced　photon　energies.　Meanwhile,　enhanced　interband　excitation　led　to　increased　electron　density　above　the　Fermi　level,　resulting　in　enhanced　optical　scattering　by　localized　surface　plasmon　resonance　(LSPR).　These　mechanisms　are　responsible　for　balancing　the　direct　heating　of　bulk　electrons　by　optical　pulses.　The　corresponding　studies　not　only　revealed　the　physics　for　the　electronic　dynamics　in　tungsten　carbide,　but　also　proposed　that　the　modified　electronic　and　electronphononic　interactions　are　one　of　the　important　responsible　mechanisms　for　the　enhanced　laser-damage　threshold　of　the　hard-metal　coating.　Furthermore,　the　nanostructured　hard-metal　coating　integrates　functions　of　enhancement　of　the　damage-threshold　and　anti-reflection　coating,　which　is　important　for　exploring　new　tools　or　materials　in　laser　engineering.　(C)　2016　Optical　Society　of　America