Gas turbine components with microchannel cooling

A component includes a substrate (110) having an outer surface (112), an inner surface and a tip (34). The inner surface defines at least one hollow, interior space. The outer surface (112) defines one or more grooves (132), where each groove (132) extends at least partially along the outer surface (112) of the substrate and has a base (134). The component further includes a coating (150) disposed over at least a portion of the outer surface (112) of the substrate (110). The coating (150) includes at least a structural coating (150) that extends over the groove(s) (132), such that the groove(s) (132) and the structural coating (150) together define one or more channels for cooling the component. The tip comprises a tip cap enclosing the hollow, interior space(s), and a tip rim disposed at a radially outer end of the substrate. The tip rim at least partially defines at least one discharge channel in fluid communication with at least one cooling channel (130).