| CPC G01N 33/2045 (2019.01) [B22F 10/28 (2021.01); B22F 10/38 (2021.01); B29C 64/00 (2017.08); B29C 64/10 (2017.08); B33Y 10/00 (2014.12)] | 20 Claims |

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1. A method of producing powdered feedstock for melt-based additive manufacture by evaluating and modifying the substructural features of a pre-alloyed bulk material having predefined chemical composition, comprising the steps of:
a. melting a defined region on the surface of a coupon of the pre-alloyed bulk material having a predefined chemical composition, using a laser at a first energy level thereby creating a first subsurface volume having a first depth;
b. obtaining a first set of structural modification measurement data associated with the first subsurface volume after allowing the first subsurface volume to solidify;
c. re-heating the defined region on the coupon using the laser at a second energy level thereby creating a second subsurface volume having a second depth, wherein the second depth may be deeper or shallower than the first depth;
d. obtaining a second set of structural modification measurement data associated with the second subsurface volume after allowing the second subsurface volume to cool to a first temperature;
e. determining whether the first and second subsurface volumes comprise one or more desirable structural characteristics, wherein the one or more desirable structural characteristics comprise the following:
i. dissolution of the constituent elements, separation of the constituent elements, redistribution of the constituent elements, separation into phases of constituent elements;
ii. changes in grain morphology, grain size, or grain size distribution;
iii. prior precipitates of constituent elements, changes in precipitate size, and precipitate spatial distribution;
iv. lack of defects such as cracks, fissures, and voids;
v. changes in crystallographic texture;
vi. changes in microhardness; and
f. rendering the pre-alloyed bulk material comprising the one or more desirable structural characteristics into a fine-grained, homogenous substructure having uniform composition.
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