Wardell has worked for four years with the England programme, spending a year as coach of U14 boys and three years as coach of the U14 and U16 girls.
The former GB international, who made 59 appearances for this country, won a bronze medal with GB in 2009 and silver in 2011.
Hartmann moves from his role with GB U20s and Brown comes across from his position with GB U16s, as the duo link up with current head coach Sean Easton.
Ashton comes across from his previous assistant coach role with GB Women and will be assisted by Essi Aittasalo and Darryl Morvan.
As well as facing the hosts Korea, GB will come up against Slovenia and a qualifier from the previous round.
The Division II Group A tournament will be held at the Dumfries Ice Bowl from 19th to 22nd January 2021.
The presentation see’s Chris Ellis joined by the coaches and players to talk through the game and discuss what was going through their headsas they came from 3-0 down draw level at 3-3 and force overtime.
These proposals will be brought up for vote by the IIHF Member National Associations (MNAs) at the 2020 IIHF Extra-Ordinary Congress, which is intended to take place in a virtual format with the target date on Wednesday, 24 June.