After participating in a week of fleet exercises in mid-January 1970, "Duchess" began a sequence of port visits: Port Swettenham, Kota Kinabalu, Manila, Bangkok, Hong Kong, Osaka (coinciding with Expo '70), Kobe, and Subic Bay before returning to Singapore. This was followed by SEATO exercises in the South China Sea during March and April. "Duchess" returned to Sydney on 5 June, and was docked for a refit, which lasted until 8 February 1971. On 18 March, "Duchess" was again deployed to the Far East. The destroyer met "Sydney" off Singapore on the troopship's nineteenth on 3 April. The two ships arrived in Vũng Tàu on 5 April, and returned to Hong Kong on 8 April. After a sequence of port visits, "Duchess" and met "Sydney" on 17 May for transportation run twenty. Vũng Tàu was reached on 22 May, with departure a day later. "Duchess" sailed to Hong Kong, then on 8 June departed for Australia, arriving on 25 May and commencing a mid-cycle docking which ran until 13 November. In January 1972, "Duchess" joined , , and for a task group deployment to Asian waters. The deployment included SEATO exercises and port visits to Port Klang and Surabaya, before the ships arrived in Fremantle on 14 April. After proceeding to Sydney for maintenance, "Duchess" resumed exercising in local waters. During a surface firing exercise on 25 July, a shell from B turret hit one of the elevated barrels of A turret. In August, with her loan period up, "Duchess" was purchased outright from the Royal Navy for GB£150,000. After a midshipman training cruise to Port Moresby in August, the ship spent the rest of the year on exercises and training.