KR materials science. Option 17

OPTION 17, tasks: 1) Select carbon steel to make reamers. Assign a heat treatment mode, describe the essence of the occurring transformations, the structure and properties of the tool. 2) As a result of heat treatment, the gears should get a solid wear-resistant surface layer with a viscous core. steel 12XH3A was selected for their manufacture. Indicate the composition and determine the steel group as intended. Assign the regime of thermal and chemical-thermal treatment, give its justification, explaining the effect of alloying on the transformations that occur at all stages of processing of this steel. Describe the structure and properties of the steel after heat treatment. 3) Describe the use of cermet hard alloys in the manufacture of dies. Indicate their structure, composition and properties. 4) For the manufacture of some parts of the aircraft, alloy V95T1 was selected. Indicate the composition and characteristics of the mechanical properties after heat treatment. Describe how this alloy is hardened and explain the nature of hardening. 5) Film materials, their variety. properties and scope in mechanical engineering.