Titanium is an amazing material offering strength, lightness of weight, and corrosion resistance but there are also instances that titanium should not be used. This brief newsletter covers the do’s and don’ts of titanium screws.
Do Use for Saltwater & Chloride Resistance
One of the most noteworthy uses of titanium screws is in saltwater environments. Naval as well as industries like desalination and offshore oil rely on titanium for their unparalleled resistance to saltwater. Titanium fasteners are resistant to both rapid moving and stagnant seawater up to a mile deep – even at temperatures of up to 500°F.
Like seawater, titanium screws are also almost inert to all chloride and chlorine solutions. This is due to titanium’s ability to rapidly regenerate its protective passive layer in the presence of oxygen. Titanium fasteners are also resistant to::
o Chlorite
o Hypochlorite (Bleach)
o Chlorate
o Perchlorate
o Chlorine dioxide
Do Use for Strength and Lightness
Titanium grade 5 offers industry impressive strength: 148 ksi UTS and 138 ksi yield. What
makes titanium’s strength truly unique is that it is also extraordinarily light. Grade 5
fasteners are 4 times stronger than 316 stainless steel at nearly half the weight. (Grade 2 titanium is approximately 2 times stronger.) This unparalleled strength-to-weight ratio make titanium ideal for medical, aerospace, and military applications.
Don’t Use in Acids
Titanium fasteners offer excellent corrosion resistance to salt water and chlorides but NOT strong acids. When exposed to acids like sulfuric (H2SO4), hydrochloric (HCl), their protective passive layer is attacked and can rapidly corrode in the right concentrations and temperatures.
Don’t Use in Dry Chlorine
Though titanium screws are ideal for almost all chloride and chlorine applications they cannot be used in the absence of water. Dry chlorine and chlorine gases will make them rapidly corrode and even ignite. Typically 1% moisture (at room temperature) and 1.5% (at high temperature) is sufficient for titanium to regenerate its passive layer and remain resistant.
In addition to its high strength-weight ratio, and saltwater and chloride resistance titanium also offers industry:
- Non-toxic, biocompatibility and osteointegration, making it ideal for medical and dental applications
- Titanium Grade 5 fasteners are non-ferromagnetic