This may come as a surprise but Leaf steel is pretty Hard and durable when it's the way it's supposed to be, but when you put an edge on it, it will not be a very good edge. one thing i learned from stock removal leaf springs is that smaller knifes are terrible if not heat treated but bigger blades that don't need to be razor sharp are OK if you don't heat treat it. but i would recommend heat treating, it's a lot of fun too see the difference between a heat treated knife and non heat treated.