The Bonarc ER309L is a premium quality austenitic stainless steel TIG welding rod designed to meet AWS A5.9 specifications. This 2.4mm filler metal is specifically formulated with a higher chromium (23-25%) and nickel (12-14%) content compared to standard 304\/308 grades. This alloy composition provides exceptional corrosion resistance and oxidation resistance at elevated temperatures. The ‘L’ designation indicates a low carbon content (maximum 0.03%), which is critical for preventing sensitization and intergranular corrosion in the heat-affected zone (HAZ) during multi-pass welding operations.<\/p>\n
Primarily engineered for welding base metals of similar composition (AISI 309\/309S), this rod is the industry standard for joining dissimilar steels, such as austenitic stainless steel to carbon or low-alloy steels. It is also extensively used for applying buffer layers on carbon steel prior to cladding with 308 or 316 grades. The metallurgical structure typically contains a controlled amount of ferrite to minimize susceptibility to hot cracking, a common issue when welding fully austenitic structures. The 2.4mm diameter offers a balanced deposition rate suitable for medium-gauge fabrication and root passes in pipe welding.<\/p>\n
Packaged in a durable 5kg tube, these rods are protected from environmental contaminants, ensuring consistent weld quality. The rods are designed for use with DCEN (Direct Current Electrode Negative) polarity and 100% Argon shielding gas to produce clean, defect-free welds with excellent mechanical properties.<\/p>\n","protected":false},"excerpt":{"rendered":"Bonarc ER309L is used for welding of 22% Cr-12% Nickel (Ni) Stainless Steel and dissimilar steels such as 304 to mild steel or low alloy steels, also used for joining dissimilar stainless steels such as 409 to itself or to 304L stainless.","protected":false},"featured_media":0,"template":"","meta":{"_acf_changed":false},"product_brand":[],"product_cat":[1964,1959],"product_tag":[],"class_list":{"0":"post-1783948","1":"product","2":"type-product","3":"status-publish","5":"product_cat-all-stainless-mig-tig-electrodes","6":"product_cat-welding-wires-and-electrodes","7":"pa_aws-spec-er309l","8":"pa_brand-bonarc","9":"pa_diameter-2-4mm","10":"pa_diameter-2-5mm","11":"pa_grade-425","12":"pa_packaging-10lb-tube","13":"pa_packaging-5kg-tube-2","14":"pa_packaging-description-5kg-tube","15":"pa_polarity-dc","16":"pa_polarity-dcen","17":"pa_weld-process-tig","19":"first","20":"onbackorder","21":"taxable","22":"shipping-taxable","23":"purchasable","24":"product-type-simple"},"acf":[],"_links":{"self":[{"href":"https:\/\/josefgases.com\/stage\/wp-json\/wp\/v2\/product\/1783948","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/josefgases.com\/stage\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/josefgases.com\/stage\/wp-json\/wp\/v2\/types\/product"}],"wp:attachment":[{"href":"https:\/\/josefgases.com\/stage\/wp-json\/wp\/v2\/media?parent=1783948"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/josefgases.com\/stage\/wp-json\/wp\/v2\/product_brand?post=1783948"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/josefgases.com\/stage\/wp-json\/wp\/v2\/product_cat?post=1783948"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/josefgases.com\/stage\/wp-json\/wp\/v2\/product_tag?post=1783948"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}