Foundry Metallurgy B.E Question Paper : jaduniv.edu.in

Name of the University : Jadavpur University
Department : Metallurgical Engineering
Degree : B.E
Subject Name : Foundry Metallurgy
Sem : II
Website : jaduniv.edu.in
Document Type : Model Question Paper

Download Model/Sample Question Paper : https://www.pdfquestion.in/uploads/dspace.jdvu.ac.in/5462-Foundry%20Metallurgy.pdf

Foundry Metallurgy Question Paper :

B. Metallurgy Engg. Part–I Examination, 2008 :
(2nd Semester)
Time : Three hours

Related : Jadavpur University Steel Making B.E Model Question Paper : www.pdfquestion.in/5461.html

Full Marks : 100
Answer any five questions. :
All questions carry equal marks. :
Assume any data, you feel necessary. :
1. a) Explain : 2×5
Clay, AFS Clay, Active Clay, Dead Clay, Ball Clay.
b) What are structures of Montmorillonite and Kaolinite ? 2×2
c) Describe the formation of clay water Bond. 4
d) What is the handicap of this bond ? 2

2. a) Explain : 2×5
Wrought iron, White iron, Chilled iron, Grey iron, Mottled iron. With their microstructures.
b) What is Coke bed ? How Cupola operator does measure the adequacy of coke bed height ? How do you light a Cupola ? What is Cupola capacity ? What is Coke rate ? 2×4+1+1

3. How do you justify the following :
(i) The height : diameter and Tayerc area : Cupola area in selecting proper Cupola Design.
(ii) High Mn Pig and High Si Pig in cast iron melting.
(iii) Cast iron is a section sensitive material.
(iv) Nickel bearing electrodes are used in cast iron welding.

(v) Low-S iron, high temperature and nodulisers are essential for ductile iron production.
(vi) Malleable iron cannot be produced in Cupola.
(vii) Sea-coal is used in cast iron foundries. 3×6+2

4. a) Deduce the relationship between, thermal supercooling and critical nucleus size during solidification of a pure metal. How does the thermal supercooling affect, from investment casting to splat cooling, in grain structure development ? 8+2

b) What is constitutional supercooling ? What is dendrite ? How does the thermal gradient change the freezing process in case of alloys ? 2×2+4
How can you distinguish between short freezing with long freezing range alloys. 2

5. How can you explain the following :
(i) Sprues are tapered.
(ii) Bottom pouring produces better castings than top pouring.
(iii) Thin sections are difficult to feed.
(iv) Zincon sand is used in investment castings.
(v) Shell molding requires metal patterns.

(vi) In plate casting, gates, away from sprue, fill the mold quick.
(vii) Molases often is used in steel castings.
(viii) Polyesterene patterns can be seen in EPC process.
(ix) Plate sections are not recommended for risering.
(x) Divided blast reduces coke rate in Cupolas. 2×10

6. a) Describe (briefly) : Jolting, Loam molding, Thixo-Castings, Steadite, Modulus. 2×5
b) Explain :
(i) Why are popular cast metals of Eutectic Composition ?
(ii) What are draw backs of sand molding ?
(iii) Why too much fines are undesirable in foundry sand ?
(iv) Why core sand does have lower GFN than molding sand ?
(v) What is AFS standard sand sample. 2×5

7. Discuss :
a) Chovorinov’s Rule, Bernoulli’s Theorem, Scab, Radiographic Testing, Misrun. 2×5
b) Derive the filling times for top and bottom gating systems and compare them. What is pressurized gating system ? What is Blind riser ? 8+1×2

Syllabus :
Foundry Metallurgy :
Introduction to foundry, Casting production. Sand & Non-sand Casting processes, Special Casting processes- Full mold, Shell molding, CO2 , Die, Investment, Centrifugal etc.

Sand molding materials, their properties, selection & testing (Grading of sand, GCS, DCS, Permeability etc)Bonding & bond mechanisms (Clay-water, Hydraulic & Organic), Selection of Foundry Clay (Bentonite Structure, Base exchange capacity & Acceptability Test,).

Additives, Mechanization of Sand molding Process,Patterns- Allowances, Types, Selection etc.  Gating Design, Laws of fluid flow, Top & Gating Time, Aspiration correction, Design of gating for a plate casting.

Riser Design(Modulus method, Geometry of risers, Directional solidification, Chill, Padding etc,) Complete Methoding Practice from Pattern to riser/gating design of individual castings.

Solidification of – Metals, Alloys & Eutectics, (Nucleation & Growth Process, Critical nucleus size, Supercooling, G/R ratio, Cell, Dendritic & Random dendritic structure, Segregation & Coring, Eutectics, Compositions in Cast Irons, FG & SG structures, Metallic Glass) .

Mold dilation, Mold-metal reactions. Structure & Section sensitivity Cast irons- family & microstructures, Alloying effects, Cupola & its operation, nodular iron and alloy cast irons. White (Malleable) Iron, ADI, Charge calculations.

Non-ferrous casting production (Silumin alloys, Liquid forging, Brass & Bronze casting) Melting furnaces (Arc, Induction, Gas & Oil fired furnaces, Fluxes). Fettling & finishing, Casting defects- Hot tears, Inclusions and porosities. NDT testing & inspection,Casting design.