Jovanovski notched her seventh break of the day in the match's next-to-last game for a 4-6, 7-6 (7-2), 6-4 win over Johanna Larsson. Earlier Zhang ousted fourth-seeded Yvonne Meusburger 6-3, 6-0.
Both Jovanovski and Zhang have won 12 of their last 13 matches, streaks that include tournament titles. Zhang won last week in Guangzhou for her first WTA championship and Jovanovski collected her second tournament win Sept. 14 in Uzbekistan.
Friday's title match will be the first meeting between the two.
Jovanovski's match with Larsson started off with four breaks before the players settled down. Jovanovski dropped her serve four times in the set but her game improved from there. She had at least two breaks of Larsson's serve in each set.
Zhang, yet to drop a set this week, was on the court just 63 minutes in beating Meusburger. She won 71 percent of the points on serve, including going 7-for-7 on Meusburger's break chances.
The winner of Friday's title match will collect $20,000 with the runner-up check worth $11,000. Larsson and Meusburger each took home $6,000 as semifinalists.
The official name of the tournament is the Yinzhou Bank Cup International Women's Tennis Open.
Reindeer recovered after escaping from Santa during lighting ceremony
Wisconsin business offering 'therapeutic cuddling' forced to close