That never happended since the Maurice Richard Trophy is awarded (1998). However, it happen that 2 teamates lead the league in goal scored before 1998, and, therefore, would have accomplished that.
1936 : Bill Thoms & Charlie Conacher, Toronto Maple Leafs, 23 goals
1955 : Maurice Richard & Bernard Geoffrion, Montreal Canadiens, 38 goals
9 times times there was ties for the scoring title, 2 of them had 3 players sharing the award (1980, 2004).