Particle compositions and related methods and uses to form sintered silicon carbide bodies
The present invention relates to a feedstock composition comprising inorganic particles having a multi-modal particle size distribution and comprising a collection of irregular fine particles having a fine particle size distribution and an average fine particle diameter, and a collection of irregular coarse particles having a coarse particle size distribution and an average coarse particle diameter that is in a range from 4 to 7 times the average fine particle diameter. The feedstock composition further comprising a binder composition that is adapted to solidify to form a body comprising the inorganic particles and solidified binder composition. Additionally, the present composition provides a method of forming a shaped body that comprises inorganic particles dispersed in binder composition as well as a method of forming a low porosity inorganic sintered body.
1 . A method of forming a shaped body that comprises inorganic particles dispersed in binder composition, the method comprising:
using feedstock composition comprising inorganic particles having a multi-modal particle size distribution, the feedstock composition comprising:
from 10 to 30 weight percent inorganic particles based on the total weight of the feedstock composition, the inorganic particles having a multi-modal particle size distribution including a collection of irregular fine particles having a fine particle size distribution and an average fine particle diameter, and a collection of irregular coarse particles having a coarse particle size distribution and an average coarse particle diameter that is in a range from 4 to 7 times the average fine particle diameter, and
from 70 to 90 weight percent binder composition, based on the total weight of the feedstock composition; and
forming the feedstock composition into a shaped body that comprises the inorganic particles and solidified binder composition.
2 . The method of claim 1 , comprising forming the feedstock composition into a shaped precursor body by an additive manufacturing step.
3 . The method of claim 1 , wherein the inorganic particles have a packing density of at least 60 percent.
4 . The method of claim 1 , wherein
the irregular fine particles have an average fine particle diameter (D50 value) in a range from 1 to 30 microns, and
the irregular coarse particles have an average coarse particle diameter (D50) in a range from 30 to 200 microns.
5 . The method of claim 1 , comprising:
from 10 to 50 weight percent irregular fine particles, and
from 50 to 90 weight percent irregular coarse particles,
based on total weight composition.
6 . The method of claim 1 , wherein
the irregular fine particles consist of silicon carbide particles, and
the irregular coarse particles consist of silicon carbide particles.
7 . A method of forming a low porosity inorganic sintered body, the method comprising:
using feedstock composition comprising inorganic particles having a multi-modal particle size distribution, the feedstock composition comprising:
from 10 to 30 weight percent of a powder composition having a multi-modal particle size distribution based on the total weight of the feedstock composition, the powder composition comprising
a collection of irregular fine particles having a fine particle size distribution and an average fine particle diameter (D50 value), and
a collection of irregular coarse particles having a coarse particle size distribution and an average coarse particle diameter (D50 value) that is in a range from 4 to 7 times the average fine particle diameter, and
from 70 to 90 weight percent binder composition, based on the total weight of the feedstock composition;
forming the feedstock composition into shaped precursor body that comprises solidified binder composition and the inorganic particles; and
heating the shaped precursor body to a temperature that causes the irregular fine particles and the irregular coarse particles to become fused together to form the inorganic sintered body.
8 . The method of claim 7 , comprising forming the feedstock composition into a shaped precursor body by an additive manufacturing step.
9 . The method of claim 7 , wherein the inorganic sintered body has a porosity below 5 percent.
10 . The method of any of claim 7 , wherein the inorganic sintered body comprises at least 97 weight percent silicon carbide.
11 . The method of claim 7 , wherein the particle composition has a packing density of at least 60 percent.