Forging , Die Casting (단조, 다이케스팅) Mass Production Forging , Die Casting (단조, 다이케스팅) © www.afdex.com 1

Impression-die forging (형단조) Workpiece acquires the shape of the die cavity while deformed between the closing dies. Forging force : also called Closed-die forging (패쇠단조) kp: pressure-multiplying factors (3~12) Die Flash Land Parting line Impression-die forging is also called closed-die forging. In impression-die forging, the metal is placed in a die resembling a mold, which is attached to the anvil. Usually the hammer die is shaped as well. The hammer is then dropped on the workpiece, causing the metal to flow and fill the die cavities. The hammer is generally in contact with the workpiece on the scale of milliseconds. Depending on the size and complexity of the part the hammer may be dropped multiple times in quick succession. Excess metal is squeezed out of the die cavities, forming what is referred to as flash. The flash cools more rapidly than the rest of the material; this cool metal is stronger than the metal in the die so it helps prevent more flash from forming. This also forces the metal to completely fill the die cavity. After forging the flash is removed. In commercial impression-die forging the workpiece is usually moved through a series of cavities in a die to get from an ingot to the final form. The first impression is used to distribute the metal into the rough shape in accordance to the needs of later cavities; this impression is called an edging, fullering, or bending impression. The following cavities are called blocking cavities, in which the piece is working into a shape that more closely resembles the final product. These stages usually impart the workpiece with generous bends and large fillets. The final shape is forged in a final or finisher impression cavity. If there is only a short run of parts to be done it may be more economical for the die to lack a final impression cavity and instead machine the final features. Impression-die forging has been improved in recent years through increased automation which includes induction heating, mechanical feeding, positioning and manipulation, and the direct heat treatment of parts after forging. Flash is the excess metal, which squirts out of the cavity as a thick ribbon of metal. The flash serves two purposes: • Acts as a ‘safety value’ for excess metal. • Builds up high pressure to ensure that the metal fills all recesses of the die cavity. One variation of impression-die forging is called flashless forging, or true closed-die forging. In this type of forging the die cavities are completely closed, which keeps the workpiece from forming flash. The major advantage to this process is that less metal is lost to flash. Flash can account for 20 to 45% of the starting material. The disadvantages of this process include additional cost due to a more complex die design and the need for better lubrication and workpiece placement.

Impression-die hot forging 1STAGE 2STAGE 3STAGE Bucket Tooth BUCKET TOOTH ©gsf.co.kr http://ma.gnu.ac.kr/vod/Forming/Hot_Forging.wmv Hot forging

Tube Hydroforming Hydraulic pump injects high pressure fluid inside a hollow tube to expand until it matches a negative mold. Strong and light structures for vehicles Dies Seals Hydraulic pressure Tube Hydroforming is a specialized type of die forming that uses a high pressure hydraulic fluid to press room temperature working material into a die. To hydroform aluminum into a vehicle's frame rail, a hollow tube of aluminum is placed inside a negative mold that has the shape of the desired result. High pressure hydraulic pumps then inject fluid at very high pressure inside the aluminum which causes it to expand until it matches the mold. The hydroformed aluminum is then removed from the mold. One of the largest applications of hydroforming is the automotive industry, which makes use of the complex shapes possible by hydroforming to produce stronger, lighter, and more rigid unibody structures for vehicles. This technique is particularly popular with the high-end sports car industry and is also frequently employed in the shaping of aluminium tubes for bicycle frames. SME: http://www.youtube.com/watch?v=nylIvins3XE

Die casting (다이캐스팅) The molten metal is forced into the die cavity by high pressure. Ejector platen (moves) Ejector die half box Ladle Stationary Shot sleeve Plunger rod Metal sleeve Cover disk Closing cylinder Pouring hole Plunger rod Shot sleeve Die casting is a manufacturing process that can produce geometrically complex metal parts through the use of reusable molds, called dies. The die casting process involves the use of a furnace, metal, die casting machine, and die. The metal, typically a non-ferrous alloy such as aluminum or zinc, is melted in the furnace and then injected into the dies in the die casting machine. There are two main types of die casting machines - hot chamber machines (used for alloys with low melting temperatures, such as zinc) and cold chamber machines (used for alloys with high melting temperatures, such as aluminum). The differences between these machines will be detailed in the sections on equipment and tooling. However, in both machines, after the molten metal is injected into the dies, it rapidly cools and solidifies into the final part, called the casting. The steps in this process are described in greater detail in the next section. ©갈창우 http://www.youtube.com/watch?v=1AgDGLNE6Es SME 90s

Die casting Can be automated for large production runs. Strength-to-weight ratio of die-cast parts increases with decreasing wall thickness. Good surface finish and dimensional accuracy. It is used for aluminium, magnesium and copper alloys. The castings that are created in this process can vary greatly in size and weight, ranging from a couple ounces to 100 pounds. One common application of die cast parts are housings - thin-walled enclosures, often requiring many ribs and bosses on the interior. Metal housings for a variety of appliances and equipment are often die cast. Several automobile components are also manufactured using die casting, including pistons, cylinder heads, and engine blocks. Other common die cast parts include propellers, gears, bushings, pumps, and valves. http://www.youtube.com/watch?v=WptzR_-o9aY

Powder Metallurgy PM1: http://www.youtube.com/watch?v=n_FW7Q2xO5o http://www.hmptech.com

Powder Metallurgy Powder production Blending or mixing(혼합) Compaction(압축) Sintering(소결) Finishing operations(마무리가공) PM2: http://www.youtube.com/watch?v=iQIsk44JUYs&feature=related http://www.youtube.com/watch?v=1Mjsi2F2MrY

Mass Production Plastic (플라스틱) Automotive fender

Plastic Injection Molding Plastics are melted in a heated cylinder and forced into a mold by hydraulic plunger of rotating screw. Complex shape and good dimensional accuracy can be achieved, as in die casting. http://www.youtube.com/watch?v=uQgc8ZZAFEs http://ma.gnu.ac.kr/vod/Plastic/Plastic_Injection_Molding.MP4

Injection Mold Die structure SLIDE CORE EJECTION PLATE EJECTION PIN RETURN PIN GUARD BUSH GUARD PIN ROCKET RING SPRUE BUSHING ANGULAR PIN CORE 돌출판 돌출핀 Die structure Injection Mold of JY-Solutec http://www.jysolutec.com

Injection molding Vacuum Cleaner: Blower: Housing Hand grip http://www.tsmould.com/cyberpr01.htm

Injection Mold

Blow molding Blow up a plastic balloon to fill the mold. http://kr.youtube.com/watch?v=grIPNOHkdOc&feature=related http://www.youtube.com/watch?v=oR0gMKN58kY&p=9B6D9EAE75875D9D