Why same casting has different hardness and machineability
properties? One spot it is found hard for machining and
another spot soft? It is FG 260 grade for Cast Iron.
Answers were Sorted based on User's Feedback
Answer / anil kamat
If it is a free flow single gate single runner casting then
the density variation leads to the diffrence in properties
across various sections. To get uniform density variation
usually pressure flow multigate multirunner castings are
preferred.
| Is This Answer Correct ? | 11 Yes | 3 No |
Answer / preethi
uneven solidification results in different grain size and
that leads to the difference in hardness. the surface of the
cast will have finer grains due to faster solidification
(comparatively high temperature gradient) than the core.
| Is This Answer Correct ? | 10 Yes | 4 No |
Answer / shashikant g. sane
The casting must have solidified with uneven cooling rates.
So the part that has cooled faster has developed extra
hardness.
| Is This Answer Correct ? | 6 Yes | 2 No |
HOW TO GET LAST 10 YRS. QUESTION PAPERS
What is d2?
Describe strain aging based on dislocation theory?
What are the materials used to manufacture Aeroplane Wings?
What is the specific speed of a pump ?
What happens when the mercury of a thermometer spills over the gold ring?
What is chemical composition and mechanical properties of IS 2004,Gr-3 and IS 305 AB-2?
what are the causes of delayed fracture in case hardened steels?
The requirement for ASTM A217 Gr. WC9 castings for valves components like Body and Bonnet were Normalising at 920+/- 20 Deg. C and Tempring 780+/- 20 Deg. C The specification calls furnace shall be calibtated within +/-14 deg. C The Heat Chart shows minimum temperature for normalising 900 to 920 Deg. C, but maximum temperature 960-990 Deg. C Tempering 780+/-20 Deg. C is within limits and accepted. Casting having integral test bars, heat trated along with castings passed in chemical znalysis and mechanical properties. Since normalising maximum temperature is not meeting specification, where castings can be salvaged or renormalised and retempered to meet specification. Whether it will have affect on remechanical properties testing
Define what are ceramics?
Is brass magnetic?
Can 1026 steel be welded?
Civil Engineering (5086)
Mechanical Engineering (4456)
Electrical Engineering (16639)
Electronics Communications (3918)
Chemical Engineering (1095)
Aeronautical Engineering (239)
Bio Engineering (96)
Metallurgy (361)
Industrial Engineering (259)
Instrumentation (3014)
Automobile Engineering (332)
Mechatronics Engineering (97)
Marine Engineering (124)
Power Plant Engineering (172)
Textile Engineering (575)
Production Engineering (25)
Satellite Systems Engineering (106)
Engineering AllOther (1379)