What is galling? It is just cold welding when metal comes in contact with another virgin metal. It is worse when you have similar metals. The mutual solid solubility determines the extent of galling - the higher the solubility limit the higher the tendency for cold welding. Stainless steel has...
Contact Dr George Vandervoort at Buehler for help:
George F. Vander Voort
Director, Research & Technology
Buehler Ltd
41 Waukegan Road
Lake Bluff, IL 60044 USA
Phone: 1-847-295-4590
Email: George.VanderVoort@BUEHLER.COM
Hi desertfox
Failure mode: Unfortunately, the fracture surface was subsequently abrased by soil and therefore of no use. It was smooth and flat - failed possibly by a brittle fracture mode.
Strength: The hardness of the bolt (40 HRc) corresponds to an ultimate tensile strength (UTS) value of...
Just to conclude this post:
The bolt was a 0.30 carbon steel with an average hardness of around 40HRc. It was possibly heat treated. The hardness readings show higher than expected for a Grade 3 bolt. I do not know why a Grade 3 bolt was made from a 0.3 C steel and heat treated when the spec...
Friction coefficient (FC) can vary as a function of applied load, speed and the environment. I have measured FC for aluminium against steel and also against itself. For Al-steel couple, FC varied from 0.4 to 0.6 whereas Al-Al 0.4 to 0.8, depending on the operating conditions.
The static FC may...
If you are working in the oil and gas industry (upstream/downstream), NACE has several books including MR0175 (check the number). It has an equivalent ISO standards book for materials selection also.
I am a bit surprised at the direction this post has taken.
I had only the head portion of a broken bolt and wanted to know what type of bolt that was. I figured out from the standards that was a Grade 3 bolt (thanks to those who helped me).
SnTman,
What kind of info do you want me to get from...
It is a plow bolt. It has a small square section under the head. The part has a square hole with a countersink.
when I post hardness readings, I will include another photo for you. Please bear with the delay.
I have received a couple of bolts with a rather unique markings for failure analysis. It has two lines on its head. There is no such markings in the standards. I attach a photo of one of the bolts. If you know any info on this bolt, please let me know. Thanks.
Vukk, please provide of actual CVN values as IRStuff says. Also, some info on the process history such as heat treatment temperature and time and microstructure would be helpful. Generally, tempered martensite has higher toughness than as rolled pearlitic/ferrite.
MikeMet, what is your hardness...
We use flame cutting on low alloy steel plates to make 6 to 12 inch wide strips. The plate moves around 0.5 inch and therefore the strips are not parallel. Did any one experience this type of movement? Any comments on how to stop this movement?
I use less than 1 h/inch for 0.30C steels up to 3 inches. It seems to be working.
Metengr, can you please give the full reference for the Penn state uni paper so that I can get a copy? Any pdf version available on the Internet?
Thank you all your valuable inputs. Sorry, I could not respond to your replies earlier.
I am in the process of actually doing some experiments to confirm your theories. Let you know in a few weeks.
Does any one have any insight into the steel microstructure (say low carbon low alloy type) that forms after quenching and tempering in a induction heat treatment line as compared to a gas fired furnace system? I am specifically interested in the influence of soaking time (more in gas fired...
Thanks to all for your replies. They are useful. I have more specific questions.
UncleSyd: You have said that it is not a good idea to work when it is at 875F. Why? I thought it has more ductility/plasticity at 875F than at room temperature. Could you please explain your thoughts.
MetEngr...
