You could look into this, but I doubt any Pi 2 kernels were built that way.
uname -a will tell you for sure.
Killing the power abruptly can cause filesystem corruption but it is actually very unlikely. It is more likely if the system is very busy at the time (which seeming "locked up" could actually mean "too busy to respond properly), but if this keeps happening over and over, there is something else going on.
If you are pulling the plug because it has locked up, you should look at
/var/log/syslog afterward to see if anything interesting is indicated there as to why it did this.
There are millions of pis and unfortunately, they were not all made perfectly. This is perhaps inevitable, or perhaps a result of insufficient testing and quality control, but either way occasionally someone is going to get a lemon. There could be a problem with the SD card reader. But first you have to rule out a few things:
The SD card itself. Get another one -- a brand new one -- and try that. If it still happens, re-format both cards however is most useful to you and put a bunch of photos or mp3s or whatever you have a bunch of on them, a least a GB or so. Then try using them as many places as you can and see if they are okay.
The power supply. I think this is not very likely as well, but you should at least try it with two different 5V supplies that are both at least 1.5 A.
If you are consistently having this problem after that, you should contact the distributor you bought this from and explain the problem and that you have tried multiple SD cards and power supplies. I do not think they will argue, but if they refuse to take it back, please let us know in a comment here who they are.