Metal Chess Set Design - MITweb.mit.edu/3.042/team1_08/finalposter.pdf · Metal Chess Set Design To...
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Metal Chess Set Design To gain experience with a wide variety of materials processing and fabrication techniques through the construction of an aesthetically pleasing and functional metal chess set. Objectives Objectives Design Design Materials Selection Materials Selection Sadik Sadik Antwi Antwi - - Boampong Boampong , Aaron , Aaron Buchok Buchok , John , John Rogosic Rogosic , Tami Jean , Tami Jean Shinkawa Shinkawa Materials Characterization Materials Characterization Methods and Construction Methods and Construction Design Constraints Design Constraints King’s height ~ 9 cm with ~ 4 - 5 cm base. Pieces proportionate in height and form Aesthetically pleasing, stable, and of comfortable weight Board Design Board Design Individual tiles were to be machined, polished, and colored from stock material. In order to lighten the overall weight of the board and the materials cost of the project, these tiles (chosen to be brass), would be inset on an aluminum base. Aluminum was chosen was for its relatively low weight and cost, as well as high stiffness. Piece Design Piece Design Pieces were chosen to be sand- cast using a single metal (such as to ensure a uniform weight on both sides) and would later be surface treated in order to obtain the necessary difference in coloration. Materials Constraints Materials Constraints Castable metal readily available as sheet stock (for board) Of “comfortable” weight Fracture and dent resistant product Surface finishing options Materials Options Materials Options Castable metals were ranked based on materials properties. Several possible candidate materials were identified including aluminum, copper alloys, and iron. Materials Choice Materials Choice Ultimately a Copper-Zinc alloy was selected for the project. The particular alloy consisted of ~ 58% Cu and 39% Zn with other trace impurities. The alloy is extremely hard and gold in color when cast (it is commonly used in Hollywood as a substitute for gold on screen), however the alloy can be somewhat difficult to cast as it is particularly sensitive to turbulent flow. SEM Analysis SEM Analysis Samples from both the as-received ingots and cast metal were taken for SEM analysis. The ingot overall composition was within 0.5% of the manufacturer specifications, and consisted primarily of alpha and beta phase materal. The cast samples on the other hand, included far less alpha phase (as expected) and were of a slightly different overall composition than the ingots. In addition to the many voids present in the material, there were peculiar iron-rich inclusions dispersed throughout the cast samples. Microstructure Microstructure Samples were taken from both the as-received ingots and the cast material, and the microstructures were compared. The ingot displayed a much higher concentration of alpha phase, suggesting that the cooling conditions under which they were formed differed from our casting process. Additionally, many more inclusions believed to be voids were present in our cast samples Investment Casting Investment Casting A ceramic powder is mixed into a slush with ethanol and poured over a wax version of the object to be cast. After solidifying, the wax material is removed through heat treatment and molten metal is poured into the cavity. One of the two major methods of casting, sand casting allows for a greater level of surface detail to be captured, and as a result was chosen for this project. Machining Operations Machining Operations The board was constructed primarily through the use of tooling, consisting of a CNC mill, lathe, and water jet. The construction was a multi-step process involving careful computer design and technical execution of the design to machine numerous pieces with high precision (to ensure an appropriate fit when the end product was assembled). Surface Treatments Surface Treatments White pieces were electroplated using a proprietary method at the Xtalic corporation. The process involves controlled deposition of nickel and tungsten atoms through the use of alternating current to fine tune the nanocrystalline surface structure of the product. Black pieces were treated with a commercially available chemical bath to form a surface oxide layer (known as a patina). Commercially available metal chess pieces Board design for both the individual tiles and inset cavity Common castable metals ranked by increasing density (to the right) and increasing stiffness (upwards) Copper-Zinc phase diagram (Left) Investment has been poured over a set of waxes within the cardboard tube and allowed to solidify for over 24 hours (typically several days). (Right) A typical pawn after being cast and removed from the investment, however before any surface touching up, polishing, or finishing has been performed. Note the small surface imperfections and air bubbles present in the raw casting. Cavity in the aluminum base is machines on a CNC mill (Left) Ni-W electroplated pieces. (Right) Patina pieces. SEM image showing beta phase (the bulk of the image), alpha phase (grey band in the lower-right quadrant), voids (black areas with a white halo around them), and an iron inclusions (black bands spaced at a 120 degree angle from each other in the center of the image) Microstructure of etched material samples. Magnification of 100x in both images. (Left) As-received metal ingot. Different grains can be seen, with the bulk of the material as beta phase and the light dendrites present are alpha phase material. (Right) Cast sample contains far less alpha phase. In addition, there are many more voids present in the material, which tend to appear most frequently at grain boundaries
Transcript of Metal Chess Set Design - MITweb.mit.edu/3.042/team1_08/finalposter.pdf · Metal Chess Set Design To...
Metal Chess Set Design
To gain experience with a wide variety of materials processing and fabrication techniques through the construction of an aesthetically pleasing and functional metal chess set.
ObjectivesObjectives
DesignDesign
Materials SelectionMaterials Selection
SadikSadik AntwiAntwi--BoampongBoampong, Aaron , Aaron BuchokBuchok, John , John RogosicRogosic, Tami Jean , Tami Jean ShinkawaShinkawa
Materials CharacterizationMaterials Characterization
Methods and ConstructionMethods and Construction
Design ConstraintsDesign Constraints
King’s height ~ 9 cm with ~ 4 - 5 cm base.
Pieces proportionate in height and form
Aesthetically pleasing, stable, and of comfortable weight
Board DesignBoard Design
Individual tiles were to be machined, polished, and colored from stock material. In order to lighten the overall weight of the board and the materials cost of the project, these tiles (chosen to be brass), would be inset on an aluminum base. Aluminum was chosen was for its relatively low weight and cost, as well as high stiffness.
Piece DesignPiece Design
Pieces were chosen to be sand-cast using a single metal (such as to ensure a uniform weight on both sides) and would later be surface treated in order to obtain the necessary difference in coloration.
Materials ConstraintsMaterials Constraints
Castable metal readily available as sheet stock (for board)
Of “comfortable” weight
Fracture and dent resistant product
Surface finishing options
Materials OptionsMaterials Options
Castable metals were ranked based on materials properties. Several possible candidate materials were identified including aluminum, copper alloys, and iron.
Materials ChoiceMaterials Choice
Ultimately a Copper-Zinc alloy was selected for the project. The particular alloy consisted of ~ 58% Cu and 39% Zn with other trace impurities. The alloy is extremely hard and gold in color when cast (it is commonly used in Hollywood as a substitute for gold on screen), however the alloy can be somewhat difficult to cast as it is particularly sensitive to turbulent flow.
SEM AnalysisSEM Analysis
Samples from both the as-received ingots and cast metal were taken for SEM analysis. The ingot overall composition was within 0.5% of the manufacturer specifications, and consisted primarily of alpha and beta phase materal.
The cast samples on the other hand, included far less alpha phase (as expected) and were of a slightly different overall composition than the ingots. In addition to the many voids present in the material, there were peculiar iron-rich inclusions dispersed throughout the cast samples.
MicrostructureMicrostructure
Samples were taken from both the as-received ingots and the cast material, and the microstructures were compared. The ingot displayed a much higher concentration of alpha phase, suggesting that the cooling conditions under which they were formed differed from our casting process. Additionally, many more inclusions believed to be voids were present in our cast samples
Investment CastingInvestment Casting
A ceramic powder is mixed into a slush with ethanol and poured over a wax version of the object to be cast. After solidifying, the wax material is removed through heat treatment and molten metal is poured into the cavity.
One of the two major methods of casting, sand casting allows for a greater level of surface detail to be captured, and as a result was chosen for this project.
Machining OperationsMachining Operations
The board was constructed primarily through the use of tooling, consisting of a CNC mill, lathe, and water jet. The construction was a multi-step process involving careful computer design and technical execution of the design to machine numerous pieces with high precision (to ensure an appropriate fit when the end product was assembled).
Surface TreatmentsSurface Treatments
White pieces were electroplated using a proprietary method at the Xtalic corporation. The process involves controlled deposition of nickel and tungsten atoms through the use of alternating current to fine tune the nanocrystalline surface structure of the product.
Black pieces were treated with a commercially available chemical bath to form a surface oxide layer (known as a patina).
Commercially available metal chess pieces
Board design for both the individual tiles and inset cavity
Common castable metals ranked by increasing density (to the right) and increasing stiffness (upwards)
Copper-Zinc phase diagram
(Left) Investment has been poured over a set of waxes within the cardboard tube and allowed to solidify for over 24 hours (typically several days). (Right) A typical pawn after being cast and removed from the investment, however before any surface touching up, polishing, or finishing has been performed. Note the small surface imperfections and air bubbles present in the raw casting.
Cavity in the aluminum base is machines on a CNC mill
(Left) Ni-W electroplated pieces. (Right) Patina pieces.
SEM image showing beta phase (the bulk of the image), alpha phase (grey band in the lower-right quadrant), voids (black areas with a white halo around them), and an iron inclusions (black bands spaced at a 120 degree angle from each other in the center of the image)
Microstructure of etched material samples. Magnification of 100x in both images. (Left) As-received metal ingot. Different grains can be seen, with the bulk of the material as beta phase and the light dendrites present are alpha phase material. (Right) Cast sample contains far less alpha phase. In addition, there are many more voids present in the material, which tend to appear most frequently at grain boundaries
