Systems and methods for improved lap shear strength and displacement of two-component structural adhesives

A system for treating a substrate, comprising:

• (a) a deoxidizing composition comprising:
• (i) a Group IVA metal and/or a Group IVB metal;
• (ii) free fluoride;
• and
• (iii) a homopolymer and/or copolymer comprising a phosphorous-containing monomeric subunit m1;
• wherein the deoxidizing composition has a pH of 1.0 to 3.0;
• and
• (b) a coating composition comprising:
• (i) a first component comprising an epoxy-containing compound;
• (ii) a second component that chemically reacts with the epoxy-containing compound, the second component comprising a diamine comprising a cyclic ring and/or a polyamine comprising a cyclic ring;
• and
• (iii) elastomeric particles.