- Видео 26
- Просмотров 58 851
Metallurgy with AJR
Индия
Добавлен 21 апр 2020
With an attempt to put my metallurgical knowledge in the automobile industry and to the common man working in an industry I present some of the most important metallurgical concepts at a glance in a simplified manner. In most of the automobile industry ,metallurgy is in its infancy. One day when I was strolling in a automobile repair shop I found out that a mechanic was heating the axle with a gas burner in order to remove the roller bearing. He doesn't know the consequences about the microstructural changes the shaft will undergo. In yet an another case an under truck chassis made of cast steel had many open blows and the surface morphology showed sand fusion. Also the material broke after a few days of service showing off a cold shut a casting defect. This shows that many manufacturing industry are more bothered about "out turn" rather than concentrating on the importance of quality control Edited and Managed by J Maxwell Dominic.Email : maxwelldomnic555@gmail.com
STRESS CORROSION CRACKING
The stress corrosion cracking is the failure of an alloy from the combined effects of a corrosive environment and static tensile stress
( the stress may result from applied forces or locked in residual stress.)
1.Chemical environment which causes SCC does not produce general chemical corrosion of the alloy.
2.SCC begins with the rupturing of the protective oxide film on the metal surface by either mechanical means or by the action of chemical species such as chloride ions.
3. Localized rupture of the surface leads in time to the formation of corrosion pits: Cracking initiates at the root of the pit( PH is different in the pit.
FRACTURE MECHANICS APPROACH
The Basic stress time curve can be ex...
( the stress may result from applied forces or locked in residual stress.)
1.Chemical environment which causes SCC does not produce general chemical corrosion of the alloy.
2.SCC begins with the rupturing of the protective oxide film on the metal surface by either mechanical means or by the action of chemical species such as chloride ions.
3. Localized rupture of the surface leads in time to the formation of corrosion pits: Cracking initiates at the root of the pit( PH is different in the pit.
FRACTURE MECHANICS APPROACH
The Basic stress time curve can be ex...
Просмотров: 8 684
Видео
Hydrogen Embrittlement
Просмотров 6 тыс.3 года назад
Severe embrittlement can be produced in many metals by very small amounts of hydrogen. Body centered cubic hexagonal closed packed metals are susceptible to hydrogen embrittlement. As little as 0.0001 wt % of hydrogen can cause cracking in steel. FCC metals are not susceptible to hydrogen embrittlement. Hydrogen is introduced during melting, entrapped during solidification and picked up during ...
JOMINY END QUENCH TEST
Просмотров 1,8 тыс.3 года назад
Determination of hardenability by Jominy end quench test or simply the End Quench Test. Edited and Managed by J Maxwell Dominic . Email: maxwelldomnic555@gmail.com
KIC FRACTURE TOUGHNESS
Просмотров 2,7 тыс.3 года назад
The discussion is about "How to fix a permissible crack length and a KIC value for a given material subjected to its designed value? Edited and Managed by J Maxwell Dominic . Email: maxwelldomnic555@gmail.com
Spheroidal cast iron/Nodular cast iron/Ductile Iron
Просмотров 3 тыс.3 года назад
Manufacturing of NCI, its types and microstructure property correlation is explained in brief. This will also be useful for students preparing for Gate exam and PSU's exam. If you like my video plz give a thumbs up...and subscribe to my channel. Use the comment section for clarifications and suggestions. Edited and Managed by J Maxwell Dominic . Email: maxwelldomnic555@gmail.com
HOT EXTRUSION OF FERROUS AND NONFERROUS ALLOYS
Просмотров 1263 года назад
There are two types of extrusion the direct and indirect types. The various parameters in extrusion process are discussed namely the extrusion ratio, optimum pressure and speed of the ram,. optimum temperature ,lubrication etc are discussed briefly. The various defects such as center bursts, fir tree cracking and coarse grain structure are also discussed in brief. This will also be useful for s...
Differentiating the black heart and white heart process for manufacturing malleable cast iron.
Просмотров 7353 года назад
Generally there are two types of Manufacturing process for malleable cast iron namely the black heart process and white heart process. The malleable irons manufactured by this methods are black heart malleable cast iron and white heart malleable cast iron respectively. Mechanical property wise the white heart malleable cast iron is superior to that of the black heart malleable cast iron. But ma...
Manufacturing of a dispersion strengthened composite through Powder Metallurgy route.
Просмотров 2653 года назад
Manufacturing of certain intricate shaped automotive components is very easy and cost effective through powder metallurgy route. There is absolute accuracy in dimensional tolerance. Certain composites such as aluminium alumina dispersion strengthened composite are tougher than steel. I have given here an over view of the process. A detailed manufacturing process can be reviewed in my published ...
ROLLING DEFECTS
Просмотров 3,8 тыс.3 года назад
Rolling defects like edge cracks centerline cracking, seams, slivers, alligatoring, longitudinal stringers, banding etc reduces the life of the certain components such as locomotive springs,suspensions, automotive components of heavy duty.A small piece of discussion is given for prevention and control of such defects. This will also be useful for students preparing for Gate exam and PSU's exam....
Prevention of corrosion in car underbodies
Просмотров 1183 года назад
Corrosion of under truck of cars is always neglected by the owners. Car maintenance involves preventive maintenance of car body. Corrosions such as pitting corrosion, exfoliation corrosion and crevice corrosion are very common to occur in the under truck of cars. I have given some tips of maintenance which keep corrosion at bay. This will also be useful for students preparing for Gate exam and ...
Normalizing an As Cast Dentritic Structure
Просмотров 2123 года назад
Normalizing an As Cast structure involves to heating the cast steel 50 degree centigrade above the upper critical temperatureAC3 in the case of hypoeutectoid steel and along the upper critical temperature Acm for a hyper eutectoid steel allowing it to remain in the furnace for a prescribed time which is dependent on the thickness of the material. The material is then flung in to the atmosphere ...
SELECTION OF BEST MICROSTRUCTURE OF GRAY IRON FOR CYLINDER LINERS.
Просмотров 1933 года назад
Selecting the best microstructure of gray iron for a particular application is a challenge for a metallurgist working in an automobile industry. Failure of cylinder liners especially in heavy duty vehicles is a subject of great concern. Even in the field of quality control there had been many arguments about the nature of microstructure and its relation to its mechanical properties such as scuf...
Quench cracking and its prevention.
Просмотров 1,7 тыс.3 года назад
Quench cracking is very common in the heat treatment industry as far as we are using water quenching and oil quenching. Drastic cooling is only required to cross past the nose of the CCT curve and to prevent diffusion. There is no need for us to have the quenchant temperature between Ms and Mf or even below Mf to get a homogeneous martensitic structure .Hence a molten salt bath can be fixed to ...
Decoding of Mechanical Failures by Visual examination of Fractured Surface.
Просмотров 7063 года назад
Failure analysis is an important subject in an Automobile industry of eminence. Knowing the root cause of the failure and implementing corrective action is the need of every uprising automobile industry .The macroscopic examination of fracture surface brings into light many of the different types of fracture modes related to fracture mechanics. The fractography using unaided microscope but perh...
Brittleness occurring during tempering.
Просмотров 4313 года назад
During tempering of bolts one should be careful in fixing the tempering temperature.Certain temperature ranges causes embrittlement such as blue brittleness and temper embrittlement. These temperature ranges should be avoided to get our desired hardness/toughness ratio.Generally during batch processing tempering of bolts uniform temperature in the furnace is a prerequisite criterion to yield be...
Microstructures of Plain Carbon Steel
Просмотров 4,3 тыс.4 года назад
Microstructures of Plain Carbon Steel
Differentiating the Microstructure of Bainite and Martensite using optical microscopy.
Просмотров 4,2 тыс.4 года назад
Differentiating the Microstructure of Bainite and Martensite using optical microscopy.
👌🏻
music is def. out of the scope, other than that thanks.
thank you
sir aap hotel reception pe video bana rahe the kya ....itna erotic music....... hor@y sir
The final fracture in SCC could be brittle or ductile, not necessarily brittle. It depends on the material of fabrication.
You are right sir.
Good job. But banding is a more complex phenomena to explain solely by the rolling process, it also involves chemical segregation of some elements in the composition of the steel.
Thank you sir
Yes sir it is a big subject to be discussed.Banding is due to the presence of segregations like MnS inclusions.I will put a separate video on that.
At normalizing for hyper-eutectoid steel heated above Acm + (40-50°C) but you are wrote heated between Ac1 and Acm . Which are correct. Sir please give answer .
Sir The normalising temperature is given above Acm and holds good.But practically if you are going above Acm for complete normalising i.e complete austenitizing the hypereutectoid steel suffers from grain growth and sometimes even cracking.Hence for all practical purposes temperature between Acm and Ac1 is followed.
@@metallurgywithajr6426 Thank you sir.
@@metallurgywithajr6426 Sir, this same phenomena occur at annealing.
Good one
can u send me thıs presentatıon ı lıke ıt :)
Thanks bro good explain
Background music is ruining the watching of videos. Music is more louder than your voice. Please recheck before uploading and excise watchers
Why background music ? This is louder than your voice. No one sees videos for listening music. Please note and edit.
Yes definitely. Thank you for your feedback.
😍
Please send to me all your presentations in your channel , I m student in mechanical department
Thanks for this video 😁 hope to remove the background music 😇
Excellent explanation Sir
Cold working decreases ductility doesn't it?
Yes definitely
Thanks for sharing, I need a quick update on the mechanisms of hydrogen embrittlement.
thanks a lot ajr
Hydrogen embrittlement is more prominent to plated and pickled parts
sir please tell some books to read these topics
Physical metallurgy by Avner and physical metallurgy by Rhagavan are good books to start with.
wrong on the explanation of pearlite.. its not combined of pearlite and cementite, its combination of ferrite and cementite..
I have explained pearlite as alternate lamellar structure of ferrite and cementite.
Nice
Watched let’s connect thanks
I get this video from my teacher on clg group 🔥
Watched❤❤❤
Thank u...
Nice
First time visitor here here to support you. You are welcome to come to our kitchen keep sharing my friend 🌷🌷🎁🔔
Sir Is fatigue testing machines available in market?
Congrats. Wonderful and crystal clear presentation and explanation.
Thank you
The video is really nice:)....I personally felt that it could have had a glimpse of the metastable state...
Watching
Good video sir.
Thank you Vinoth.