Q1: What is a Heat Treatment Furnace?
Ans: A Heat Treatment Furnace is a device used to heat metals or alloys to specific temperatures to change their physical and mechanical properties such as hardness, strength, and ductility.
Q2: Name Heat Treatment Equipment.
Ans: Heat treatment equipment includes:
- ➔ Batch Furnaces
- ➔ Continuous Furnaces
- ➔ Gas Furnaces
- ➔ Electric Furnaces
- ➔ Pit Furnaces
- ➔ Salt Bath Furnaces
Q3: What is Decarburization?
Ans: Decarburization is the loss of carbon from the surface layer of steel when heated in contact with oxygen or certain atmospheres, reducing hardness at the surface.
Q4: Name different furnaces used for Heat Treatment.
Ans: Furnaces used for heat treatment include:
- ➔ Batch Furnace
- ➔ Continuous Furnace
- ➔ Gas Furnace
- ➔ Electric Furnace
- ➔ Pit Furnace
- ➔ Lead Bath Furnace
- ➔ Salt Bath Furnace
Q5: What is a BATCH Furnace?
Ans: A Batch Furnace is a type of heat treatment furnace where materials are processed in discrete batches rather than continuously.
Q6: State the types of BATCH Furnace.
Ans: Types of Batch Furnace:
- ➔ Horizontal Gas Fired Batch Furnace
- ➔ Vertical Batch Type Furnace
- ➔ Vertical Batch Type Salt Bath Furnace
- ➔ Lead Bath Furnace
Q7: What is a Horizontal Gas Fired Batch Type Furnace?
Ans: It is a batch furnace with a horizontal chamber heated by gas burners, used for uniform heating of materials in a batch process.
Q8: What is a Vertical Batch Type Furnace?
Ans: A vertical batch type furnace is a furnace where materials are loaded vertically, often used for small components requiring uniform heating.
Q9: What is a Vertical Batch Type Salt Bath Furnace?
Ans: It is a vertical batch furnace where materials are heated by immersing them in a molten salt bath for rapid and uniform heating.
Q10: What is a Lead Bath Furnace?
Ans: A Lead Bath Furnace heats materials by immersing them in molten lead, providing uniform temperature for heat treatment of metals like steel.
Q11: What is a Continuous Furnace?
Ans: A Continuous Furnace is a furnace where materials are moved through the heating zone continuously on conveyors or rollers, allowing large-scale production.
Q12: What is a Gas Furnace?
Ans: A Gas Furnace is a furnace heated by burning natural gas or other fuels, commonly used in batch and continuous heat treatment processes.
Q13: What is an Electric Furnace?
Ans: An Electric Furnace is a furnace heated electrically using resistance or induction, providing precise temperature control for heat treatment.
Q14: What is a Pit Furnace?
Ans: A Pit Furnace is a furnace built into the ground (pit) where materials are loaded vertically and heated, often used for large workpieces.
Q15: What is a Pyrometer?
Ans: A Pyrometer is an instrument used to measure high temperatures in furnaces or heated materials without contact.
Q16: State the working principle of a Pyrometer.
Ans: Working Principle: Pyrometers measure temperature by detecting thermal radiation (infrared energy) emitted by a hot object or by using a thermocouple.
Q17: State the parts of a Pyrometer.
Ans: Parts of a Pyrometer:
- ➔ Sensor (Thermocouple or detector)
- ➔ Telescope or optical system
- ➔ Control box or display unit
- ➔ Connecting wires or circuitry
Q18: State the types of a Pyrometer.
Ans: Types of Pyrometers:
- ➔ Radiation Pyrometer
- ➔ Optical Pyrometer
- ➔ Contact Pyrometer (Thermocouple type)
Q19: Define Radiation Pyrometer.
Ans: A Radiation Pyrometer measures temperature by detecting the thermal radiation emitted by a hot object without contacting it.
Q20: Define Optical Pyrometer.
Ans: An Optical Pyrometer measures the temperature of hot objects by matching the brightness of a filament with the observed object through an optical system.
Q21: State the parts of Optical Pyrometer.
Ans: Parts of an Optical Pyrometer:
- ➔ Telescope
- ➔ Filament
- ➔ Control Box
- ➔ Power Supply
- ➔ Connecting Cables
Q22: Define Telescope.
Ans: Telescope in a pyrometer is an optical system used to view the hot object and compare its brightness with the filament or detector.
Q23: Define Control Box
Ans: Control Box houses the electronics of the pyrometer, allowing calibration, adjustment, and display of measured temperature.
Q24: What is a Thermo Couple?
Ans: A Thermocouple is a temperature measuring device made by joining two dissimilar metals, producing a voltage proportional to the temperature difference.
Q25: Name the alloys used for Thermo Couple.
Ans: Alloys used for thermocouples include:
- ➔ Iron-Constantan
- ➔ Copper-Constantan
- ➔ Chromel-Alumel
- ➔ Platinum-Rhodium
Q26: What is EMF?
Ans: EMF (Electromotive Force) is the voltage generated by a source such as a battery or thermocouple when no current is flowing.
Q27: What is Hot Junction?
Ans: A Hot Junction is the point in a thermocouple where two dissimilar metals are joined and exposed to the temperature to be measured.
Q28: What is Junction Block?
Ans: A Junction Block is a device that connects the hot and cold junctions of a thermocouple and provides stable wiring to the measuring instrument.
Q29: What is Extension Leads?
Ans: Extension Leads are wires made of similar metals as the thermocouple to extend the connection between the junction and measuring instrument without introducing errors.
Q30: What is Dry Cell?
Ans: A Dry Cell is a portable electrochemical cell that provides a source of electrical energy using a paste electrolyte instead of a liquid.
Q31: What is a Metallurgical Microscope?
Ans: A Metallurgical Microscope is a specialized microscope used to study the microstructure of metals and alloys.
Q32: What is the magnifying power of Metallurgical Microscope?
Ans: The magnifying power of a Metallurgical Microscope is usually between 50x to 2000x, depending on the objective and eyepiece used.
Q33: Name the parts of Metallurgical Microscope.
Ans: Parts of Metallurgical Microscope:
- ➔ Eyepiece
- ➔ Objective Lenses
- ➔ Stage
- ➔ Focus Adjustment Knobs
- ➔ Mirror or Light Source
- ➔ Condenser
- ➔ Base
Q34: Briefly explain the working principle of Metallurgical Microscope.
Ans: Working principle of Metallurgical Microscope:
- ➔ Direct light onto the polished metal surface.
- ➔ Light reflects from the metal surface.
- ➔ Reflected light passes through the objective lens.
- ➔ Eyepiece magnifies the image for observing the microstructure.
Q35: What is Vertical Illumination?
Ans: Vertical Illumination is a method of lighting where light is directed perpendicularly onto the specimen, commonly used in metallurgical microscopy for reflective surfaces.
Q36: Define Temperature.
Ans: Temperature is a measure of the degree of hotness or coldness of a body, indicating the thermal energy of its particles.
Q37: Define Absolute Temperature.
Ans: Absolute Temperature is the temperature measured from absolute zero (0 K), where all particle motion theoretically stops.
Q38: Define Rheostat.
Ans: A Rheostat is a variable resistor used to control current in a circuit by adjusting its resistance.
Q39: Define Galvanometer.
Ans: A Galvanometer is an instrument used to detect and measure small electric currents by the deflection of a needle.
Q40: Define Potentiometer.
Ans: A Potentiometer is a device used to measure unknown voltages by balancing them against a known voltage without drawing current from the source.
Q41: What is Black Body radiation?
Ans: Black Body Radiation is the electromagnetic radiation emitted by an ideal object that absorbs all incident radiation at all wavelengths.
Q42: State the function of the eye-piece of the microscope.
Ans: The Eyepiece magnifies the image formed by the objective lens and allows the user to view the specimen comfortably.
Q43: Briefly explain the Resolving Power of Objectives.
Ans: Resolving Power is the ability of the objective lens to distinguish two closely spaced points as separate; higher resolving power gives clearer and sharper images.
Q44: Define Oxidation.
Ans: Oxidation is a chemical reaction in which a substance loses electrons or combines with oxygen.
Q45: Define Reduction.
Ans: Reduction is a chemical reaction in which a substance gains electrons or loses oxygen.
