ASTM C365 is a test method that determines the compressive strength and modulus of sandwich core specimens. These sandwich constructions can include core materials with continuous bonding surfaces such as balsa wood and foam, as well as those with discontinuous bonding surfaces such as honeycomb. The properties are determined in the same direction the sandwich core will face during use, but this test method can also be applied to determine compressive forces in different directions if those results are desired. The goal of the test is to calculate results for the ultimate flatwise compressive strength, the stress at 2% deflection, and the compressive chord modulus. Determination of the compressive strength and modulus of sandwich cores are absolutely critical to the design of sandwich panels, which are mainly used in the aircraft industry, but are also seeing adoption in the transportation, automotive, and construction industries.
