An 18-month labour dispute at an aluminum smelter in Quebec controlled by Alcoa Corporation ended after workers accepted a deal, defying the recommendation of their union’s leadership. On Tuesday, about 80% of workers at the Becancour plant voted to ratify the offer after a meeting of the United Steelworkers in Trois-Rivieres, Quebec, the union said. Alcoa last week said it expects the smelter, which has been operated by managers at a fraction of its capacity, to be fully operational within ten months if the offer was accepted.