11 votes

Why does corrosion take place at certain stressed regions?

One of the mechanism that affect corrosion is known in the literature as Stress Corrosion Cracking (SCC). The idea is that tensile stressed regions are prone to crack development. Crack development ...
  • 22.9k
9 votes
Accepted

What metal material to use for stove exhaust pipe?

It depends on flue gas temperature. High temperature $(>250\ \textrm{C})$: use galvanized steel. Low temperature $(<250\ \textrm{C})$, use stainless steel or PVC as appropriate. See below for ...
  • 3,981
7 votes
Accepted

Does weathering steel corrode the same as carbon steel when it doesn't develop a protective patina?

In a situation where the environment does not allow the patina to form, does weathering steel perform any differently than carbon steel? Weathering steel is specifically designed to form a protective ...
  • 3,587
7 votes
Accepted

Do I need to worry about galvanic corrosion when inserting a steel bar through aluminium?

Very probably, no. Galvanic corrosion required the existence of a reactive and conductive medium, which you don't have. If there is some (for example, at least moist air, or similar) best you can do ...
  • 2,374
7 votes

Do I need to worry about galvanic corrosion when inserting a steel bar through aluminium?

Aluminum and steel are very near to each other in the Galvanic Series for seawater. So even if your apparatus is exposed to a corrosive environment along those lines, it should not corrode very ...
  • 261
7 votes
Accepted

How do protective coatings affect the lifetime of bridges?

If you are really considering catastrophic failure, what you are asking actually has several parts. The first is the coatings aspect, the second is the metal structure, the third is the connections, ...
  • 652
6 votes

How do protective coatings affect the lifetime of bridges?

The goal of using protective coating/paint is to reduce corrosion of the metal framework. The degree of corrosion varies from the top to sea level and depends on several parameters such as salinity of ...
5 votes

What kind of protection should I give structural steel in a natatorium (swiming pool) environment?

Safety issues in a "natatorium" (swimming pool) environment include the following: 1) Chlorine and other high acid gases that can corrode the steel. Both galvanization and paints/coatings can help, ...
  • 685
5 votes

Would a sacraficial anode be used to protect large boat (aircraft carrier) or is there something different?

" Something different". Impressed current, very likely using titanium anodes , and the hulls have coatings/paint to reduce necessary current flow. Navy vessels can be relatively fast , so ...
  • 5,967
5 votes

Influence of design on corrosion control

A is worse because the item holds water. Holding water resuults in corrosion, certainly near the surface. C sheds water so it will normally be dry. Accumulation of impurities seems a needlessly ...
  • 4,953
4 votes

Electrochemical protection for corrosion

I believe what you are suggesting is impressed current corrosion protection. It is used commonly in pipeline and underground storage tank applications. Example ICCP is superior to sacrificial ...
4 votes

Do I need to worry about galvanic corrosion when inserting a steel bar through aluminium?

Wikipedia defines galvanic corrosion as: "Galvanic corrosion is an electrochemical process in which one metal corrodes preferentially to another when both metals are in electrical contact, in the ...
  • 685
4 votes

What type of stainless steels can resist 6 months under the sea?

For this type of use and to make it simple we will calculate the Pitting resistance equivalent number. This is based upon the material composition. PREN = 1 x %Cr + 3.3 ( %Mo + 0.5 x %W ) + 16 x %N ...
  • 161
4 votes
Accepted

Why does corrosion take place at certain stressed regions?

In the real world ,I don't believe I have seen CORROSION at STRESSED areas. Corrosion may be accelerated at STRAINED areas; the strains introduce energy to the microstructure which may promote ...
  • 5,967
4 votes

Sacrificial Anode Marine Growth / Biofouling

The anodes may develop fouling but they still work. Most often they are aluminum , possibly alloyed ( eg. Galvalum ). The protected steel builds up a "calcareous" protective surface layer ...
  • 5,967
4 votes
Accepted

Aluminium Bolt in Titanium Casing: Any Dangers of (Contact-)Corrosion?

Galvanic Compatibility Often when design requires that dissimilar metals come in contact, the galvanic compatibility is managed by finishes and plating. The finishing and plating selected facilitate ...
  • 7,696
3 votes
Accepted

Chloride corrosion of carbon steel pipe

Corrosion can usually, but not always, be modeled as a 0-th order reaction which means linear with time. ASME B31 piping code treads lightly into this, mainly discussing factors to be used when ...
  • 5,323
3 votes

What kind of protection should I give structural steel in a natatorium (swiming pool) environment?

The presence of a swimming pool in a natatorium causes a few unique issues that most buildings do not experience: High humidity levels - Water is everywhere and is frequently sprayed. Most buildings ...
  • 10.7k
3 votes

What kind of protection should I give structural steel in a natatorium (swiming pool) environment?

Most stainless steels contain nickel around 10%. It is combined normally with chrome and molybdenum. The main problem, that a natatorium (i.e. swimming pool) is a highly corrosive environment, and ...
  • 2,374
3 votes

Will a sacrificial anode protect any length of metal that it is connected to?

There isn't necessarily a distance limit. Basically you are preventing galvanic corrosion via use of zinc which has a higher electric potential than the metals you are trying to protect. The corrosion ...
3 votes

Electrochemical protection for corrosion

There are two options: a passive method and an active method. The Passive method is to use a sacrificial zinc anode. The zinc corrodes instead of the metal that it is attached to. More information ...
  • 10.7k
3 votes

What metal material to use for stove exhaust pipe?

Just to add some unique engineering solutions that are used, depending upon applications: Brick works wonders - it resists the acid in the smoke well and can withstand the heat. Not metal, but well ...
  • 5,323
3 votes

Can I safely cook on High temperature paint?

I wouldn't try for my kitchenware. I would strongly advice against it. The main problem is that you'd be in danger of digesting high temperature paint. Even though some of them might be inert, we'd ...
  • 22.9k
3 votes

What aluminum grade is the most resistant to corrosion in alkaline environment?

None, 3003 is listed as better general corrosion resistance but it makes little difference which aluminum alloy is used in a seriously corrosive.
  • 5,967
2 votes

What metal material to use for stove exhaust pipe?

what is the most appropriate metal material i should use to avoid excessive corrosion in the exhaust pipe of the stove? If you're looking for corrosion protection, stainless steel is hard to beat. ...
  • 3,587
2 votes

Will ammonia vapor corrode 304SS?

Following Paper gives Corrosion rate for 304 SS in Ammonia + Water Vapor environment:- Louis Caruso, Harold Mitchels,"Resistance of copper-nickel alloys to ammonia corrosion in simulated steam ...
2 votes

What type of stainless steels can resist 6 months under the sea?

I would say Thibd's answer excellent. However, one should look at the cost (including fabrication) on Monel, Incoloy 825, any Inconel or Hastelloy or Titanium . Although not "steel" they are metals ...
  • 5,967
2 votes

Are brass and copper utensils safe for humans to eat from?

It always depends on the concentration and where you place the copper within the human body. In my opinion, the most interesting example are implants which are coated with copper and implanted ...
  • 139
2 votes

Does the pressure due to corrosion in concrete depends on degree of corrosion?

I'd say the mistake is assuming infinite stiffness for concrete and steel so only the rust has a strain. In reality, rust is probably the stiffest material involved, and you will get a better ...
  • 1,278

Only top scored, non community-wiki answers of a minimum length are eligible