en ساخت Manufacturing پژوهشي Research Drying temperature of the flux at normal atmosphere has a crucial role in brazing quality in automotive aluminum-based heat exchangers. Over the course of this research, NOCOLOK^&reg;flux consists of two phases of K₂AlF₅.H₂O and KAlF₄ with melting point around 580 &deg;C was used. A flux slurry was applied on the base metal, and dried at 220, 300 and 380 &deg;C in air. Mechanical assessment revealed that when flux dried at 300 &deg;C, the joint withstands maximum shear stress of 44 MPa with complete bonding. At 220 &deg;C and 380 &deg;C, joint shear stresses are 34 MPa, 30 MPa respectively. 380 &deg;C dry-off temperature under nitrogen gas improved shear strength to 39 MPa. Taking dry-off temperature as 300 &deg;C the amount of defective heat exchangers was reduced from 6% to 2% on a daily basis.<br> &nbsp; Brazing of Aluminum, NOCOLOK® Flux, Aluminum-Silicon 3381 3393 http://ase.iust.ac.ir/browse.php?a_code=A-10-444-1&slc_lang=en&sid=1 Seyyed Ali Akbar Hashemi Milani aliakbarmilani2@gmail.com 180031947532846003615 180031947532846003615 No sahand university of technology Reza Tavangar tavangar@sut.ac.ir 180031947532846003616 180031947532846003616 Yes sahand university of technology Maziyar Azadbeh azadbeh@sut.ac.ir 180031947532846003617 180031947532846003617 No sahand university of technology Ibrahim Kahinpoor engineering@irradiator.com 180031947532846003618 180031947532846003618 No Iran Radiator Co. Hossein Sadeghi-Nasab engineering3@irradiator.com 180031947532846003619 180031947532846003619 No Iran Radiator Co.