Both material have the same main composition.
The suffix L denotes low carbon, the suffix Ti denotes addition of Titanium. These modifications are useful for avoiding sensitization, that is precipitation of Chromium carbides along grain boundaries while welding, a condition prone to intergranular corrosion attack.
The modifications do not change the relative resistance to corrosion attack of the base material.
Producers might suggest other materials like Duplex stainless steels, capable of similar or better corrosion resistance in the specified environments.
