Anyone else tried these bolts yet, if so are they magnetic?
Some other bolt kit links
I wonder what type and grade of stainless they use
- Austenitic, or 300 series, stainless steels make up over 70% of total stainless steel production. They contain a maximum of 0.15% carbon, a minimum of 16% chromium and sufficient nickel and/or manganese to retain an austenitic structure at all temperatures from the cryogenic region to the melting point of the alloy. A typical composition of 18% chromium and 10% nickel, commonly known as 18/10 stainless, is often used in flatware. 18/0 and 18/8 are also available.
stainless steels, such as alloy AL-6XN
and 254SMO, exhibit great resistance to chloride pitting and crevice corrosion because of high molybdenum
content (>6%) and nitrogen additions, and the higher nickel content ensures better resistance to stress-corrosion cracking versus the 300 series. The higher alloy content of superaustenitic steels makes them more expensive. Other steels can offer similar performance at lower cost and are preferred in certain applications, for example ASTM A387 is used in pressure vessels but is a low alloy carbon steel with a chromium content of 0.5% to 9%. [sup]
[/sup] Low-carbon versions, for example 316L or 304L, are used to avoid corrosion problems caused by welding. Grade 316LVM is preferred where biocompatibility
is required (such as body implants and piercings).[sup]
[/sup] The "L" means that the carbon content of the alloy is below 0.03%, which reduces the sensitization effect
(precipitation of chromium carbides at grain boundaries) caused by the high temperatures involved in welding.
- Ferritic stainless steels generally have better engineering properties than austenitic grades, but have reduced corrosion resistance, because of the lower chromium and nickel content. They are also usually less expensive. They contain between 10.5% and 27% chromium and very little nickel, if any, but some types can contain lead. Most compositions include molybdenum; some, aluminium or titanium. Common ferritic grades include 18Cr-2Mo, 26Cr-1Mo, 29Cr-4Mo, and 29Cr-4Mo-2Ni. These alloys can be degraded by the presence of σ chromium, an intermetallic phase which can precipitate upon welding.
stainless steels are not as corrosion-resistant as the other two classes but are extremely strong and tough, as well as highly machinable
, and can be hardened by heat treatment. Martensitic stainless steel contains chromium (12–14%), molybdenum (0.2–1%), nickel (less than 2%), and carbon (about 0.1–1%) (giving it more hardness but making the material a bit more brittle). It is quenched and magnetic.
stainless steels have corrosion resistance comparable to austenitic varieties, but can be precipitation hardened
to even higher strengths than the other martensitic grades. The most common, 17-4PH
, uses about 17% chromium and 4% nickel. The Lockheed-Martin Joint Strike Fighter
is the first aircraft to use a precipitation-hardenable stainless steel—Carpenter Custom 465
—in its airframe.
- Duplex stainless steels have a mixed microstructure of austenite and ferrite, the aim usually being to produce a 50/50 mix, although in commercial alloys the ratio may be 40/60. Duplex stainless steels have roughly twice the strength compared to austenitic stainless steels and also improved resistance to localized corrosion, particularly pitting, crevice corrosion and stress corrosion cracking. They are characterized by high chromium (19–32%) and molybdenum (up to 5%) and lower nickel contents than austenitic stainless steels.
The properties of duplex stainless steels are achieved with an overall lower alloy content than similar-performing super-austenitic grades, making their use cost-effective for many applications. Duplex grades are characterized into groups based on their alloy content and corrosion resistance.