Name: Carriage bolts Square Neck
Description: Round head bolt with a square neck under the head, and a unified thread pitch, made from austenitic alloy stainless steel or medium carbon alloy steel and heat-treated.
Applications: Bolts shall be heat-treated, oil or water-quenched, at the option of the manufacturer, and tempered at a minimum temperature of 800° F.
Grade 8 carriage bolts shall be heat-treated, oil-quenched and tempered at a minimum temperature of 800° F.
Same design advantages as a low carbon carriage bolt but for use in environments which require general atmospheric corrosion resistance.
The austenitic alloys develop their strength through work hardening during the fastener manufacturing process, as seen from the hardness properties below. The only heat treatment normally available on austenitic stainless alloys is annealing, which is done at approximately 1900°F to a dead soft condition and is not normally thermally reversible.
Material: 18-8 stainless steel carriage bolts are made from one of the following austenitic alloys: 302 HQ, 303, 303Se, 304, XM7, AISI 1030 - 1050 or equivalent steel.Medium carbon alloy steel