He may need to see a sleep specialist. Even if he doesn't want to go to the doctor, there may be an underlying problem that needs to be addressed.
I have night terrors of the violent kind and sleep walk as well. For me, I experience these episodes more frequently when I am especially stressed or hormonal - like postpartum - so my doctors feel it is linked to hormones. My husband has had to soothe me back to sleep many times and I usually have no recollection. Most of the time I'm looking for a baby in the bed when there isn't one but sometimes I have attacked my husband thinking he was a stranger or monster or alien or something else that is just ridiculous - he tells me I yell at him "get away from me you scary monster/alien/ghost/etc"! It's totally irrational and thankfully my husband is able to laugh it off - apparently my attack skills are very lacking! Even though I usually do not remember what happened, I do remember the fear that I felt when the night terror is happening. It is very real and very gripping.
When he is sleep walking, it is best not to wake him as its is very disorienting. It is better to let him wake up on his own or gently guide him back to bed. For the night terrors, my hubby has had success in talking to me very calmly and telling me that the baby is in his own bed (our son is now 2) or that he has scared the bad guy away. It sounds so silly in the daytime, but I swear when they are happening I believe that there is SOMETHING trying to hurt me or get to my family. Maybe you could use these techniques if your husband starts to be violent again.
Anyway, since there are some cases where a partner has severely beaten or even raped (meaning sex that wasn't consensual) their loved one while asleep and have no memory of the act, I would encourage you to have your hubby seek help immediately out of concern for your safety and for the overall health of your relationship - I'm sure neither of you want to face each night wondering what will happen.
One thing that may help convince him to go and would also help the doctors is to keep a log of when he walks or thrashes out in his sleep. Since there are so many things that can lead to sleep disturbances I think it is very important to have it checked out - it's a very common problem and is nothing to be ashamed about :)
Best of luck to you and your family!