Respected sir,

ASTM D 638 for FRP composite

I am sorry I don't specialize in honeycomb compression structure.

I'm assuming you want to opt for compression-compression fatigue. To be frank, I have often thought about this question for my research and ended up deriving my own answers out of seeing a lot of literature.

You need to follow the same specification as you follow for a fully solid fatigue specimen, except that the transition between the gripper portion(fully solid) to the gauge area(honeycomb) should be gradual. Otherwise, the results will not be accurate. A good example can be found in this article:

https://www.nature.com/articles/s41598-018-23414-2

Though, the above work is done for titanium alloy, a lot of conceptual understanding can be obtained from it that can be utilized for a polymeric sample as well. Do think about it and let me know if you need further insights in this regard. I'm also in the learning stage

I think you can use ASTM C393-62, you can recheck before u do use this answer.

As of my knowledge cutoff in September 2021, there is no specific ASTM standard for conducting fatigue compression tests on 3D printed polymer-based honeycomb structures. However, ASTM standards such as ASTM E466-15a for metallic materials and ASTM D7791-19 for plastics can be referenced and adapted for fatigue testing. Custom testing protocols may need to be developed to suit the specific geometry and material properties of the 3D printed honeycomb structures. Consulting with experts in materials engineering or testing laboratories familiar with 3D printing and polymer materials can provide further guidance on establishing appropriate testing procedures.

ASTM D6828 is the ASTM standard for fatigue compression testing of 3D printed polymer-based honeycomb structures.

although the ASTM D6828-(2) 2019 can be used it is designed for textile fabrics and would need to be modified to suit

you would be best using ASTM D638-22for this test