Search results
Results from the WOW.Com Content Network
In metallurgy, cold forming or cold working is any metalworking process in which metal is shaped below its recrystallization temperature, usually at the ambient temperature.. Such processes are contrasted with hot working techniques like hot rolling, forging, welding, etc. [1]: p.375 The same or similar terms are used in glassmaking for the equivalents; for example cut glass is made by "cold ...
Cold working generally results in a higher yield strength as a result of the increased number of dislocations and the Hall–Petch effect of the sub-grains, and a decrease in ductility. The effects of cold working may be reversed by annealing the material at high temperatures where recovery and recrystallization reduce the dislocation density.
The most important industrial uses are softening of metals previously hardened or rendered brittle by cold work, and control of the grain structure in the final product. Recrystallization temperature is typically 0.3–0.4 times the melting point for pure metals and 0.5 times for alloys.
2. Cold-Weather Workouts. A workout in cold temperatures can also induce chills quickly, especially when you push hard and then stop. Active muscles produce heat, but once you stop exercising ...
Plastics and low-melting-temperature metals, including many solders, can begin to creep at room temperature. Glacier flow is an example of creep processes in ice. [3] The effects of creep deformation generally become noticeable at approximately 35% of the melting point (in Kelvin) for metals and at 45% of melting point for ceramics. [4]
This process is mainly suited for low-carbon steel. The material is heated up to a temperature just below the lower critical temperature of steel. Cold-worked steel normally tends to possess increased hardness and decreased ductility, making it difficult to work. Process annealing tends to improve these characteristics.
Cryogenic hardening is a cryogenic treatment process where the material is cooled to approximately −185 °C (−301 °F), typically using liquid nitrogen.It can have a profound effect on the mechanical properties of certain steels, provided their composition and prior heat treatment are such that they retain some austenite at room temperature.
The green, orange and yellow lines indicate how surface temperatures will likely respond if leading carbon emitters begin to reduce reliance on fossil fuels. Without immediate curbs, temperatures are set to follow the red track, and increase between 3.2 and 5.4 degrees Celsius by 2100. The green line shows how we can minimize warming if ...