Deficit of data about parameters, which you search, caused by high  reaction ability of Ammonium Perchlorate (AP). For example, when we pressed the sample (tablet) of AP in compression test, the risk of explosion exist (remember the incident in Nevada, USA in 1988) . I think, this circumanstance explains the lack of data about mechanical properties of AP.  Way out, may be, in testing of small quantity of this compound.       

three articles are attached for your perusal. may be useful.

Hi Mustaq,

Thanks for the sources but unfortunately none of them seem to have the details I require. The first one talks about explosive properties,  second about cleavage and crystallography and the third about the propellant properties overall.

The cleaving process is a low energy fracture process

I am in full agreed with collegue Mushtaq Ahmad.  Nevertheless, may I try to recommend you, dear Sharanya Dulasiraman, to atract brave men and organise relatively simple mechanical test to get the failure parameters of AP in a safe, conditions (using defence means and small size specimen)?  Minimization of fracture energy is recommended (for example, using nothced samples and moistening. Good luck, Serge