After using industrial CT to review hundreds of "printed" Ti parts, the prior above comment regarding differentials from batch to batch could not be more correct. The issue is caused by a lack of control over the purity of the powder material. All it takes is are a couple of tiny impure grains, which result in a 'pop corn' effect during the processing. Each layer is not visible or inspected, so the defect becomes encased by surrounding melted material and the resulting void is now invisible. If each part is CT scanned, and qualified showing no porosity in critical structural areas, this may be satisfactory for non structural parts. The downside is CT inspection is time consuming (10-15 min per part); the upside is a diminished skilled worker demand. At a recent symposium showcasing all the major 3D metal print firms along with the major aerospace fabricators, curiously there were NO Quality or CT firms invited or exhibiting. Not being a conspiracy theorist, but it does make one want to say hmmmm.
We now can conduct virtual structural analyses on the actual geometry of the printed metal part, defects and all, using the CT voxel based dataset. Doing porosity analyses is completely automated as well on the same dataset. This is a young industry. Save your $$ fabricating non structural parts til the process track record and material control is proven to be magnitudes greater than I have seen so far for mission critical parts. Printed metal biological replacement parts such as hip sockets, joints, knees, and spinal parts are ideal for this young industry in that the force loading is quite a bit less, and can tolerate porosity; wing spar supports, turbine blades, engine mounts, NFW.
these two guys are focusing on many organic items, that in time will degrade. It is a pity that the article did not stress that aspect. Yeah, 3D printing is the new buzz, but being able to document the geometry of things that crumble with time and oxidation is a service that is invaluable.
I use http://www.mindmapper.com/ to quickly capture topics and associated tasked and info. If I need to schedule, resource, or cost, just use the drop downs to append info. If I need to put it into MS Project, just export. It also does simple outlines as well as PowerPoint.
The best part is that I can add topics and then drag them into the appropriate order at any time; no having to think of order while capturing info.
when did "old" become a negative?
you now learn things from people younger than you?
wow, things have certainly changed!
I guess knowledge was over rated.
now, get off my lawn.
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After using industrial CT to review hundreds of "printed" Ti parts, the prior above comment regarding differentials from batch to batch could not be more correct. The issue is caused by a lack of control over the purity of the powder material. All it takes is are a couple of tiny impure grains, which result in a 'pop corn' effect during the processing. Each layer is not visible or inspected, so the defect becomes encased by surrounding melted material and the resulting void is now invisible. If each part is CT scanned, and qualified showing no porosity in critical structural areas, this may be satisfactory for non structural parts. The downside is CT inspection is time consuming (10-15 min per part); the upside is a diminished skilled worker demand. At a recent symposium showcasing all the major 3D metal print firms along with the major aerospace fabricators, curiously there were NO Quality or CT firms invited or exhibiting. Not being a conspiracy theorist, but it does make one want to say hmmmm. We now can conduct virtual structural analyses on the actual geometry of the printed metal part, defects and all, using the CT voxel based dataset. Doing porosity analyses is completely automated as well on the same dataset. This is a young industry. Save your $$ fabricating non structural parts til the process track record and material control is proven to be magnitudes greater than I have seen so far for mission critical parts. Printed metal biological replacement parts such as hip sockets, joints, knees, and spinal parts are ideal for this young industry in that the force loading is quite a bit less, and can tolerate porosity; wing spar supports, turbine blades, engine mounts, NFW.
these two guys are focusing on many organic items, that in time will degrade. It is a pity that the article did not stress that aspect. Yeah, 3D printing is the new buzz, but being able to document the geometry of things that crumble with time and oxidation is a service that is invaluable.
I use http://www.mindmapper.com/ to quickly capture topics and associated tasked and info. If I need to schedule, resource, or cost, just use the drop downs to append info. If I need to put it into MS Project, just export. It also does simple outlines as well as PowerPoint. The best part is that I can add topics and then drag them into the appropriate order at any time; no having to think of order while capturing info.
I'm sorry Dave, I can't do that.
when did "old" become a negative? you now learn things from people younger than you? wow, things have certainly changed! I guess knowledge was over rated. now, get off my lawn.