1. Fundamental of Materials Forming
-Special Casting

2. Special Casting Expendable-pattern Casting(Lost Foam) 消失模铸造
Ceramic Mold Casting 陶瓷型铸造
Investment Casting 熔模铸造
Die Casting 压力铸造
Centrifugal Casting 离心铸造
Squeeze Casting 挤压铸造

3. Different Casting Processes
Advantages
Disadvantages
Examples
Sand
many metals, sizes, shapes, cheap
poor finish & tolerance
engine blocks, cylinder heads
Shell mold
better accuracy, finish, higher production rate
limited part size
connecting rods, gear housings
Expendable
pattern
Wide range of metals, sizes, shapes
patterns have low strength
cylinder heads, brake components
Plaster mold
complex shapes, good surface finish
non-ferrous metals, low production rate
prototypes of mechanical parts
Ceramic mold
complex shapes, high accuracy, good finish
small sizes
impellers, injection mold tooling
Investment
complex shapes, excellent finish
small parts, expensive
jewellery
Permanent mold
good finish, low porosity, high production rate
Costly mold, simpler shapes only
gears, gear housings
Die
Excellent dimensional accuracy, high production rate
costly dies, small parts,
non-ferrous metals
gears, camera bodies, car wheels
Centrifugal
Large cylindrical parts, good quality
Expensive, few shapes
pipes, boilers, flywheels

4. Pentane 戊烷 polystyrene 聚苯乙烯
Ferrous 铁 aluminum 铝 hot melt 热溶性
adhesive 粘合剂 coat涂上
refractory slurry 耐火泥浆
bonding agents 黏结剂 compact 压实
Ablation process 烧蚀过程
heat degrade(depolymerizes) 热降解
Polymer 聚合体 thermal gradients 温度梯度
Manifold 歧管
PMMA polymethyl methacrylate 聚甲基丙烯酸甲酯
Polyalkylene 聚(亚烷基)
Metal-matrix composite 金属基复合材料
grain refinement 晶粒细化

5. Figure Schematic illustration of the expendable pattern casting process, also known as lost foam or evaporative casting.

6. Ceramic Molds陶瓷型铸造
Figure Sequence of operations in making a ceramic mold. Source: Metals Handbook, vol. 5, 8th ed.

7. Figure A typical ceramic mold (Shaw process) for casting steel dies used in hot forging. Source: Metals Handbook, vol. 5, 8th ed.

8. Slurry 浆
zircon 锆
fused silica 熔融硅
volatile 挥发物
shaw process 萧氏硬度
Fireclay 耐火土
clay 黏土
Firebrick 耐火砖

9. Investment Casting
特种铸造之三
Figure Schematic illustration of investment casting, (lost-wax process). Castings by this method can be made with very fine detail and from a variety of metals. Source: Steel Founders' Society of America.

10. Investment Casting of a Rotor
Figure Investment casting of an integrally cast rotor for a gas turbine.
(a) Wax pattern assembly. (b) Ceramic shell around wax pattern. (c) Wax is melted out and the mold is filled, under a vacuum, with molten superalloy. (d) The cast rotor, produced to net or near-net shape. Source: Howmet Corporation.

11. Investment and Conventionally Cast Rotors
Figure Cross-section and microstructure of two rotors: (top) investment-cast; (bottom) conventionally cast. Source: Advanced Materials and Processes, October 1990, p. 25 ASM International

12. ethyl silicate 硅酸乙酯
slurry 涂浆料
Slurry coating 浆料涂层
Stucco coating 粉刷
Crystallization 结晶化
Fine detail 微细节
high-melting-point alloy 高熔点合金
Cam 凸轮
Valve 阀门
Ratchet 棘齿
Ceramic-shell investment casting 陶瓷壳精密铸造

13. Vacuum-Casting Process
Figure Schematic illustration of the vacuum-casting process. Note that the mold has a bottom gate. (a) Before and (b) after immersion of the mold into the molten metal. Source: From R. Blackburn, "Vacuum Casting Goes Commercial," Advanced Materials and Processes, February 1990, p. 18. ASM International.

14. Pressure Casting
Figure (a) The bottom-pressure casting process utilizes graphite molds for the production of steel railroad wheels. Source: The Griffin Wheel Division of Amsted Industries Incorporated. (b) Gravity-pouring method of casting a railroad wheel. Note that the pouring basin also serves as a riser. Railroad wheels can also be manufactured by forging.

15. Hot- and Cold-Chamber Die-Casting
Figure (a) Schematic illustration of the hot-chamber die-casting process. (b) Schematic illustration of the cold-chamber die-casting process. Source: Courtesy of Foundry Management and Technology.

16. Cold-Chamber Die-Casting Machine
Figure (a) Schematic illustration of a cold-chamber die-casting machine. These machines are large compared to the size of the casting because large forces are required to keep the two halves of the dies closed.

17. Hot-Chamber Die-Casting Machine
Figure (b) 800-ton hot-chamber die-casting machine, DAM 8005 (made in Germany in 1998). This is the largest hot-chamber machine in the world and costs about $1.25 million.

18. Die-Casting Die Cavities
Figure Various types of cavities in a die-casting die. Source: Courtesy of American Die Casting Institute.
Figure Examples of cast-in- place inserts in die casting. (a) Knurled bushings. (b) Grooved threaded rod.

19. Die-Casting Examples
(a)
(b)
Figure (a) The Polaroid PDC-2000 digital camera with a AZ91D die-cast, high purity magnesium case. (b) Two-piece Polaroid camera case made by the hot-chamber die casting process. Source: Courtesy of Polaroid Corporation and Chicago White Metal Casting, Inc.

20. Casting Examples Figure 11.3 A cast transmission housing.
Figure Typical gray-iron castings used in automobiles, including transmission valve body (left) and hub rotor with disk-brake cylinder (front). Source: Courtesy of Central Foundry Division of General Motors Corporation.
Figure A cast transmission housing.

21. Centrifugal Casting Process
Figure Schematic illustration of the centrifugal casting process. Pipes, cylinder liners, and similarly shaped parts can be cast with this process.

22. Semicentrifugal Casting
Figure (a) Schematic illustration of the semicentrifugal casting process. Wheels with spokes can be cast by this process. (b) Schematic illustration of casting by centrifuging. The molds are placed at the periphery of the machine, and the molten metal is forced into the molds by centrifugal force.

23. Squeeze-Casting
Figure Sequence of operations in the squeeze-casting process. This process combines the advantages of casting and forging.

24. Single Crystal Casting of Turbine Blades
Figure Methods of casting turbine blades: (a) directional solidification; (b) method to produce a single-crystal blade; and (c) a single-crystal blade with the constriction portion still attached. Source: (a) and (b) B. H. Kear, Scientific American, October 1986; (c) Advanced Materials and Processes, October 1990, p. 29, ASM International.

25. Single Crystal Casting
Figure Two methods of crystal growing: (a) crystal pulling (Czochralski process) and (b) the floating-zone method. Crystal growing is especially important in the semiconductor industry. Source: L. H. Van Vlack, Materials for Engineering. Addison-Wesley Publishing Co., Inc., 1982.

26. Melt Spinning
Figure Schematic illustration of melt-spinning to produce thin strips of amorphous metal.

27. Types of Melting Furnaces
Figure Two types of melting furnaces used in foundries: (a) crucible, and (b) cupola.