Use app×
Join Bloom Tuition
One on One Online Tuition
JEE MAIN 2025 Foundation Course
NEET 2025 Foundation Course
CLASS 12 FOUNDATION COURSE
CLASS 10 FOUNDATION COURSE
CLASS 9 FOUNDATION COURSE
CLASS 8 FOUNDATION COURSE
0 votes
125 views
in Science by (115k points)
closed by
The type of case hardening using 50% charcoal, BaCO3, CaCO3 at a temperature close to 950 degrees is ________ carburising.
1. pack
2. gas
3. liquid
4. liquid and gas

1 Answer

0 votes
by (114k points)
selected by
 
Best answer
Correct Answer - Option 1 : pack

Explanation:

Carburising: 

  • Carburising is a thermochemical process in which carbon is diffused into the surface of low carbon steels to raise the carbon content to levels high enough for the surface to react to heat treatment and form a strong, wear-resistant layer.
  • There are three different forms of carburizing:
    1. Solid (pack) carburizing
    2. Liquid carburising (or cyaniding)
    3. Gas carburising

Each form of carburizing is explained as follows

Sr. No.

Type of carburizing

Method

1

Solid (pack) carburizing

The components are enclosed by a carburizing medium and mounted in a sealed box in solid or pack carburizing. Coke or charcoal mixed with barium carbonate is often used as the medium. Temperatures range from 790 to 845°C for periods ranging from 2 to 36 hours.

2

Liquid carburizing (or cyaniding)

The component is placed in a salt bath at a temperature of 845 to 955°C to carburize it with liquid or cyanide. The salt is normally a combination of cyanide, chloride, and carbonate, and it is extremely poisonous.

3

Gas carburizing

The component is held in a furnace with a neutral carrier gas, usually a mixture of N2, CO, CO2, H2, and CH4, and a methane or propane atmosphere.


  • Nitriding is a heat treatment that introduces nitrogen into a metal's surface, resulting in a case-hardened surface. The most common steels for these processes are high-carbon, low-alloy steels.

  • Nitriding, unlike heating and quenching, requires lower temperatures and does not require a quenching process, resulting in less distortion.

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

Categories

...