Mechanical Engineering Questions

True or False:During the forging process, the coarse grain structure is broken up and replaced by finer grains; Gas porosity (inherent in the cast metal) is consolidated through the reduction of the ingot

Hot Forging: the metal to be heated above its _____ temperature

_____ involves shaping metal by applying compressive forces using a hammer, press, or die. The metal is typically heated to a high temperature to make it more malleable before being shaped

True or False:Sand molding is the oldest form of casting.

If the gas is trapped in the mold the small voids form within the casting material. ______ occurs when gases are trapped during the casting process or the die is poorly venting

____ is a process in which molten metal flows by gravity or pressure into a mold (die, tooling) where it solidifies in the shape of the mold cavity.

Green sand molds are held together by a mixture of ___ & _____Common mix: ___% sand (typically lake), ___% clay, ___% water Readily reusable by replacing the ____.

As the metal cools and transitions from a liquid to a solid state, it undergoes a decrease in volume. If this volume reduction is not compensated for properly, voids will form within the casting, resulting in _______

_______ also known as pressing, involves forming metal sheets or strips by applying mechanical force using a punch and die set. The metal is typically cold or hot worked to achieve the desired shape

the ____ mold is usually made of metal and consists of two (or more) sections that can be opened to permit removal of the finished part

______ is a mold in which the molten metal solidifies must be destroyed in order to remove the casting

______ is a mold that can be used over and over to produce many castings

In ___________, a torch is used to heat metal to its kindling temperature. A stream of oxygen is then trained on the metal ,burning it into a metal oxide that flows out of the kerf as dross

_____ is used for tooling for many mechanical processes like diecasting dies, forging dies, and sheet metal stamping dies

_____ uses a high velocity stream of Ultra High Pressure Water30,000-90,000 psi (210-620MPa) to cut materials

Water jet cutting: - Greater Thickness, Less Accuracy and needs to make ____- Difficult to cut thin materials because of _____

________ - erosion of work material by a high velocity stream of abrasives or fluid (or both)

________ electrochemical energy to remove material (reverse of electroplating)

Every "cutting process removes a different amount of material, or kerf. The more precise processes, like _____ and _____,remove a smaller amount of kerf

______ chemical etchants selectively remove material from portions of work part, while other portions are protected by a mask