Release agent-free aluminium strip casting

A method, comprising:

• drawing an aluminium alloy melt into a casting gap of at least one revolving chill mould in a strip casting system such that a surface of at least one casting roller or belt of the at least one revolving chill mould contacts the aluminium alloy melt or an oxide layer of the aluminium alloy melt;
• casting an aluminium alloy strip from the aluminium alloy melt;
• wherein the surface of the at least one casting roller or belt has a roughness value Sa of more than 5 μm measured according to DIN-EN-ISO 25178-2:2012 and an average peak count RPc (0.5 μm) of less than 42 cm−1 measured according to DIN EN 10049:2005 (application group 1—without further removal of ripple and fine roughness proportions).

A method for manufacturing an aluminium alloy strip using a strip casting system comprising at least one revolving chill mould with a casting gap, wherein the at least one revolving chill mould has at least one casting roller or belt, wherein a surface of the at least one casting roller or belt has a roughness value Sa of more than 5 μm measured according to DIN-EN-ISO 25178-2:2012 and an average peak count RPc (0.5 μm) of less than 42 cm-1 measured according to DIN EN 10049:2005 (application group 1—without further removal of ripple and fine roughness proportions), the method comprising the following steps:

• forming a melt pool of an aluminium alloy melt in a casting region in front of the at least one revolving chill mould;
• stabilising an oxide layer on the surface of the melt pool by applying an oxygen-containing gas mixture to the aluminium alloy melt;
• drawing the oxide layer into the casting gap.