No, Apple uses AES encryption (like everyone else). This encryption scheme uses a variant of either 128, or 256 bits.
That gives the encryption key a possibility of 2^128, or 2^256 different combinations.
A supercomputer (or good gamer laptop) can brute force walking through every possible combination in a given period of time.
What Apple does is if the a "hacker" attempts to crack the security key it wipes the phone after a given number of attempts.
The Government wants Apple to disable that feature while they brute force the phone confiscated from that creep.
I don't think current tech can realistically brute force AES 128bit
http://www.eetimes.com/document.asp?doc_id=1279619
