MATERIAL PROCESSING SYSTEMS
Material processing systems are disclosed. Some systems include methods of eliminating or reducing defects in elongate workpieces that can undergo large deformations during processing. Some systems include apparatus configured to facilitate such large deformations while maintaining internal stresses (e.g., tensile stresses) below a threshold stress. Some disclosed systems pertain to powder extrusion techniques. Continuous and batch processing systems are disclosed.
1 - 53 . (canceled)
54 . A continuous, elongate, consolidated form formed by a method, the method comprising:
introducing into a densifying apparatus a continuous, elongate, workpiece comprising a shaped feedstock oriented transversely to a direction of gravity;
continuously densifying the workpiece to produce a continuous consolidated article.
55 . The continuous form of claim 54 , wherein at least a portion of the workpiece is positioned such that its length is greater than a straight line distance along a centerline longitudinally bisecting the portion before introducing the portion into the densifying apparatus.
56 . The continuous form of claim 54 , wherein the feedstock comprises one or more of a powder metal, a powder ceramic, and a plastic.
57 . The continuous form of claim 54 , wherein the method further comprises substantially continuously supporting the workpiece with a support member configured to introduce the workpiece into the densifying apparatus.
58 . The continuous form of claim 55 , wherein the straight line distance along the centerline is about the same as a length of the portion following densification of the portion, such that a corresponding portion of the consolidated form is substantially straight after densification.
59 . The continuous form of claim 57 , wherein the method further comprises finishing a segment of the workpiece subsequent to densification of the segment.
60 . The continuous form of claim 54 , wherein the method further comprises extruding the feedstock through an extrusion die, supporting a portion of the workpiece on a support member and inducing relative movement between the extrusion die and the support member to orient the shaped feedstock transversely to a direction of gravity.
61 . A continuous, elongate, powder-extruded article formed by a method comprising:
sinuously positioning a first portion of an elongate workpiece such that a length of the first portion is greater than a straight line distance along a centerline longitudinally bisecting the first portion and orienting the sinuously positioned first portion transversely to a direction of gravity, wherein the workpiece comprises a shaped feedstock; and
concurrently with the act of sinuously positioning the first portion, densifying a second portion of the workpiece to produce a portion of a consolidated article; wherein a straight line distance along a centerline bisecting the second portion is about the same as a length of the portion of the consolidated article, such that the portion of the consolidated article is substantially straight after densification.
62 . An article according to claim 61 , wherein the feedstock comprises one or more of a powder metal, a powder ceramic, and a plastic.
63 . An article according to claim 61 , wherein the method further comprises extruding the feedstock through an extrusion die to produce the first portion.
64 . An article according to claim 61 , further comprising debinding the second portion before densifying the second portion.
65 . A powder extruded article comprising:
a sinuously arranged extruded, elongate, green form defining a first article portion; and
a densified second article portion contiguous with the first article portion.
66 . An article according to claim 65 , wherein a length of the sinuously arranged green form extending between two points is greater than a straight-line distance between the two points.
67 . An article according to claim 65 , wherein the densified second article portion comprises a debound segment of the sinuously arranged, elongate green form, defining a sinuously arranged, elongate brown form.
68 . An article according to claim 67 , wherein the densified second article portion further comprises a sintered segment of the brown form, defining a finished portion of the article, wherein the sinuous arrangement of the green form and the brown form facilitate longitudinal shrinking of one or both of the green form and the brown form without fracturing.
69 . An article according to claim 66 , wherein the extruded, elongate green form is produced in part by extruding a feedstock through an extrusion die to define the extruded, elongate, green form, supporting the extruded, elongate, green form on a support member, and moving the support member away from the extrusion die slower than the green form is ejected from the extrusion die.
70 . An article according to claim 65 , wherein the extruded, elongate, green form comprises an extrudate of a feedstock comprising one or more of a metal powder, a ceramic powder, and a plastic.
71 . An article according to claim 70 , further comprising a finished third portion contiguous with the densified second portion.
72 . An article according to claim 71 , wherein the relative movement between the support member and the extrusion die comprises an oscillating transverse movement relative to a direction of movement of the green form from the die, a non-oscillating transverse movement relative to a direction of movement of the green form from the die, a longitudinal movement of the support member relative to the extrusion die, and a combination thereof.
73 . An article according to claim 65 , wherein the method further comprises:
continuously extruding feedstock to form the extruded, elongate, green form;
continuously densifying the green form to produce a densified article; and
continuously finishing the densified article to produce a finished article.