Ultrasonic consolidation Hybrid printer

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An ultrasonic consolidation printer machine is one of the more interesting options for a full strength material printer. It could print in metals, plastics and maybe ceramics and it's main advantage over other methods that involve melting is that it does the material fusion in the solid state. The materials in the weld zone do not usually get hotter than about half their melting point.

Therefore, it may be better WRT not distorting the already-machined lower layers (which is important since they are supposed to be dimensionally finished) or to what extent they are distorted it may be easier to predict and compensate for the distortion.

I have done a bunch of research on this through google scholar and patents and the web and will post the notes soon. It looks promising. Also need to make sure this page, the metal deposition head page, and the multimaterial printer page are put in the right place on the wiki. Greenatolsecondtry 10:28, 28 August 2011 (UTC)



intro Okay my computer deleted the page I had written here so I am only going to make this much shorter this time.

Basically ultrasonic consolidation is particularly interesting because it involves much less heat and no melting and therefore much less distortion of lower layers without a treatment of the material deposited, and has already been worked out pretty well and gives good bonding between layers, 80 to 100% strength of the base material even.

Since it is imprecise each layer or batch of layers will be followed by a subtractive milling step (so hybrid additive/subtractive)

Contents

goals and overview

The goal of this project is to get some real manufacturing capability into the hands of real people. For now the system will be relatively small to keep prototyping costs ;down but still must be precise and output parts with good material properties, especialy metal parts from tool steels. The main thing is to demonstate that that can be done and make it open so the processes and details are available to be built upon.

Precision should be UTC5 or so, more is better. Materials should include tool steel, other steel, that's the main thing, but it should be adaptable to a wide range of materials once other hackers get their hands on the hardware.

Also should be capable of printing itself to as large an extent possible.

library research

Substrate in Ultrasonic Consolidation http://edge.rit.edu/edge/P10551/public/SFF/SFF%202006%20Proceedings/Manuscripts/48-Zhang.pdf

Ultrasonic Consolidation This is the html version of the file http://edge.rit.edu/content/P10551/public/SFF/SFF%202006%20Proceedings/Manuscripts/45-Robinson.pdf. Google automatically generates html versions of documents as we crawl the web.

Ultrasonic Consolidation

Improving Linear Weld Density in Ultrasonically Consolidated Parts

  • A Friction-Based Finite Element Analysis

of Ultrasonic Consolidation http://www.aws.org/wj/supplement/wj0708-187.pdf

and Direct Write http://edge.rit.edu/content/P10551/public/SFF/SFF%202009%20Proceedings/2009%20SFF%20Papers/2009-13-Hernandez.pdf

  • Page 1

TITLE PAGE OPTIMAL PLACEMENT OF METAL FOILS IN ULTRASONIC CONSOLIDATION PROCESS thesis very long

http://etd.lib.clemson.edu/documents/1181668872/umi-clemson-1261.pdf
  • Modeling & Manufacturing of Multi-Functional

MMCs through Ultrasonic Consolidation composite materials https://globalhub.org/resources/1066/download/Yang.pdf

Integrating UC and FDM to Create a Support Materials Deposition System

There are more to be found that are not as interesting and probably more on the next 100 results page too. There are many patents as well that may be handy but I have not bothered to collect, just search for them through freepatentsonline.com. You can search for the ones assigned to solidica by searching AN/solidica

patent issues

Solidica inc. patented the deposition method in 2002 or so , these are the first 2 patents assigned to solidica inc. (chronologically, just search AN/solidica ) [[1]] http://www.freepatentsonline.com/6463349.html so if the patent lasts 7 years it is expired now.

initial decision making

Basically the cost is the main thing, so the whole thing should be small and may be slow but must provide parts with good precision and material properties.

  • hydrostatic and aerostatic bearings give motion substantially more precise than their own machining so use those, need to check what the precision needed for aerostatic bearings is again but utc5 can do hydrostatic ones for sure. Provides good precision and low friction too.
  • Basically a single cartesian robot with different tool heads, the use of hydrostatic bearings allows effective and precise force transmission for the welding. The papers indicate that 400 newtons (40 kg) is suitable for a 4 mm diameter spot.
    • importance: designed for precision and predictability first. Then stiffness (very important too), then speed and reach. Small size helps a lot
    • the tool heads can attach/detach, or they can rotate into position.
    • the mill should have an automatic bit changer of some sort? maybe leave that till a subsequent version.
    • the mill should be 5 axis
  • definitely needs support material and the material shoudl ideally extend to the top of the print plane when desired, especially at the edges.. When printing an overhanging edge the force is high enough that the edge must be supported by material
    • what material? should be very rigid, easy to remove and reasonably easy to deposit (FDM or syringe is good) as well as relatively easy to machine. Should be low viscosity so it can be deposited anywhere the mill can reach and needs to stand the temperatures of printing too.
  • for now the bottom of leaders probably can't be machined very well. See methods mentioned elsewhere for machining leaders.
    • also could fabricate the tip of hooks in a separate area of the build volume, then pick and place them upside down in the right place. Coudl have alignment pegs machined into both the tip of the hook and the support mateiral, and epoxy or otherwise glue the hook in place to the support material (glue should be easily removable). with the glue only touching the areas that are already dimensionally finished. Then can proceed to mill the pegs away and continue building.
    • maybe could build it in near net shape, then machine under it in a small area (so the support material is removed in the process) and then inject support material back in, then machine another small area, etc. but that might screw up the positioning relative to the main object. However again as long as it is predictable practically to the desired degree then maybe it woudl be okay.
  • can use relatively thick layers rather the 150 micron foils normally used as long as the 5 axis mill is available. That would increase build speed and make manufacture of the foil easier maybe
    • want to be able to recycle the waste materials, but separating the support materials from the build material waste might be a problem, there woudl have to be a separate machine that does that part.
    • for support material, could be a very low viscosity material that just flowed like water. That would allow relatively easy deposition with a needle like nozzle. The main problem is that we want to be able to put support material quite close to the upper surface of te build layer but not get any matereial on the upper surface because it woudl get in the way of bonding the next layer on. The layer coudl eb milled after any time there is a risk of any support material getting on the top but that woudl wear the mill and take time. Coudl be done only in situations where steep overhangs need to be made I guess to keep things manageable.
  • material builds up on the solotrode so it may have to be removed with a dedicated widget

Support material option: maybe abrade the foil in the right place or only lighly consolidate it so it can be shaken apparrt later for removal. OR could use a separate sheet/foil of material that is easy to remove maybe ans use the same material as the build material, but then how to machine the sides and redeposit... well could be used in combination with FDM and actually would solve the problem of printing directly side by side to some degree (desirable in order to provide support for ledges VThe titanium sonotrode surface has been roughened so that there is no slipping between the top surface of the aluminum foil and the sonotrode during vibration. the past[74-76]. Previous research has also established that the part strength in the Ultrasonic Consolidation process, reduces considerably beyond a height to width ratio of 1:1[24] from the thesis one, but there was one of the other ones that investigated this phenomenon and concluded it was due to destructive interference and coudl be changed buy changing the frequency of ultrasound problem: mmigh tnot beable to apply a foil layer and consolidate where choose to , for some reason they alwyas seem to use bands, maybe the magnitude of motion is actually too much but check those patents again, coudld still use roller maybe modified to ensure even contace

  • have a tool to remove the excess foil and blow away the milling chips, coudl also have a pick and place tool vacuum operated maybe 2 fingered. Coudl be the TROBOT or similar, or built into the cartesian bot yeah probably better as the main thing here is to get the unceertian partts wroked out, ther si no doubt the scrap can be removed one way or another.