modeling width of weld in saw with adding nano material

one of the important methods of welding is submerged arc welding. special features of this method give it an important position among other ways. prediction the mechanical features of materials in welding zone is known as an important subjects in mechanical science. as thequality of welding has a direct relation with mechanical properties of materials, studying and predicting the factor of quality is very important. certainly bead width is one of the effective factors because it shows chemical effects and metallurgical structures and micro structures. the most important property of this research is representing anempiricalformula with high accuracy for modeling the bead width as an factor of quality of welding in submerged arc welding in which the input factors of arc voltage,current, nozzle to plate distant, welding speed, and the thickness of zno nano particles. on this research central composite rotatable matrix method is used in five level-five factor. for achieving this empirical formula with high accuracyrsm is used.