Methods of fabricating turbine engine components

A method of fabricating a component having a directionally solidified microstructure or a single crystal microstructure, the method comprising the steps of:

• depositing a nickel-base superalloy powder with a composition comprising gamma nickel solid solution and gamma prime (Ni3Al) solid solution phases onto a seed crystal, the seed crystal having a predetermined primary orientation;
• fully melting the deposited nickel-base superalloy powder and a portion of the seed crystal at a superliquidus temperature to form an initial layer, the initial layer having the predetermined primary orientation;
• heat treating the deposited layer at subsolvus temperatures to precipitate particles of the gamma prime solid solution phase;
• depositing additional nickel-base superalloy powder over the initial layer;
• melting the deposited additional nickel-base superalloy powder and a portion of the initial layer at a superliquidus temperature to form a successive layer, the successive layer having the predetermined primary orientation;
• heat treating the successive layer at a subsolvus temperature to precipitate particles of the gamma prime solid solution phase;
• and
• repeating the steps of depositing additional nickel-base superalloy powder, melting the deposited additional nickel-base superalloy powder and the portion of the successive layer at the superliquidus temperature, and heat treating the successive layer at the subsolvus temperature to form the component.