Spheroidal titanium metallic powders with custom microstructures
Methodologies, systems, and devices are provided for producing metal spheroidal powder products. By utilizing a microwave plasma, control over spheriodization and resulting microstructure can be tailored to meet desired demands.
1. A method of modifying at least one of particle shape or microstructure of a titanium based feed stock, the method comprising:
selecting a composition of the titanium based metal feed stock;
determining a desired microstructure for a final product;
selecting cooling process parameters based upon the desired microstructure and selected composition of the titanium based metal feed stock;
melting at least a surface portion of particles of the titanium based metal feed stock in a plasma having a substantially uniform temperature profile at between 4,000K and 8,000K to spheroidize the particles;
exposing the spheroidized particles to an inert gas; and
setting and applying the selected cooling processing parameters to create spheroidized particles with the desired microstructure,
wherein the cooling process parameters comprise one or more of a cooling gas flow rate, a residence time of the titanium based metal feed stock, and a cooling gas composition,
wherein the titanium based metal feed stock has a α-phase crystal structure and the spheroidized particles includes one or more regions of a β-phase crystal structure.
2. The method of claim 1 , wherein selecting the composition of the titanium based metal feed stock comprises determining an alloying composition of a titanium based feed stock source.
3. The method of claim 1 , wherein the particles of the titanium based metal feed stock have a particle size of no less than 1.0 micrometers and no more than 300 micrometers.
4. The method of claim 1 , wherein setting and applying the selected cooling processing parameters comprises controlling a cooling gas flow rate.
5. The method of claim 1 , wherein setting and applying the selected cooling processing parameters comprises controlling a residence time of the particles of the titanium based metal feed stock in the plasma.
6. The method of claim 1 , wherein setting and applying the selected cooling processing parameters comprises controlling a cooling gas composition.
7. The method of claim 1 , wherein the cooling processing parameters are selected to create a martensitic microstructure in the spheroidized particles.
8. The method of claim 1 , wherein the cooling processing parameters are selected to create a Widmanstätten microstructure in the spheroidized particles.
9. The method of claim 1 , wherein the cooling processing parameters are selected to create an equiaxed microstructure in the spheroidized particles.
10. The method of claim 1 , wherein the cooling processing parameters are selected to create at least two regions in the spheroidized particles, each region having a different microstructure or crystal structure.
11. The method of claim 10 , wherein the at least two regions include a core portion and a skin portion.
12. The method of claim 11 , wherein the skin portion has a microstructure that is different from the microstructure of the titanium based metal feed stock.
13. A method of modifying at least one of particle shape or microstructure of a titanium based feed stock, the method comprising:
selecting a composition of the titanium based metal feed stock;
determining a desired microstructure for a final product;
selecting cooling process parameters based upon the desired microstructure and selected composition of the titanium based metal feed stock;
melting at least a surface portion of particles of the titanium based metal feed stock in a plasma having a substantially uniform temperature profile at between 4,000K and 8,000K to spheroidize the particles;
exposing the spheroidized particles to an inert gas; and
setting and applying the selected cooling processing parameters to create spheroidized particles with the desired microstructure,
wherein the cooling process parameters comprise one or more of a cooling gas flow rate, a residence time of the titanium based metal feed stock, and a cooling gas composition,
wherein the titanium based metal feed stock has a single phase structure and the spheroidized particles have a multiphase structure.
14. The method of claim 13 , wherein selecting the composition of the titanium based metal feed stock comprises determining an alloying composition of a titanium based feed stock source.
15. The method of claim 13 , wherein the particles of the titanium based metal feed stock have a particle size of no less than 1.0 micrometers and no more than 300 micrometers.
16. The method of claim 13 , wherein setting and applying the selected cooling processing parameters comprises controlling a cooling gas flow rate.
17. The method of claim 13 , wherein setting and applying the selected cooling processing parameters comprises controlling a residence time of the particles of the titanium based metal feed stock in the plasma.
18. The method of claim 13 , wherein setting and applying the selected cooling processing parameters comprises controlling a cooling gas composition.
19. The method of claim 13 , wherein the cooling processing parameters are selected to create a martensitic microstructure in the spheroidized particles.
20. The method of claim 13 , wherein the cooling processing parameters are selected to create a Widmanstätten microstructure in the spheroidized particles.
21. The method of claim 13 , wherein the cooling processing parameters are selected to create an equiaxed microstructure in the spheroidized particles.
22. The method of claim 13 , wherein the cooling processing parameters are selected to create at least two regions in the spheroidized particles, each region having a different microstructure or crystal structure.
23. The method of claim 13 , wherein the at least two regions include a core portion and a skin portion.
24. The method of claim 23 , wherein the skin portion has a microstructure that is different from the microstructure of the titanium based metal feed stock.