| 摘要 |
PURPOSE:To produce a polyolefin coated steel material having sufficient adhesive force and property using flame spray without preheating by coating a pretreated steel material with epoxy primer, flame-spraying thereafter polyolefin having adhesive property of MI>=7 and spraying polyolefin having an adhesive property of MI<=5 thereon. CONSTITUTION:A pretreatment such as sandblast is applied to a steel material and then primer 1 is applied thereto to form a film of 10-100mum in thickness. After the primer 1 has been sufficiently cured, polyolefin 2 having an adhesive property of MI>=7 is sprayed thereon to form a film 100-300mum in thickness. The polyolefin 2 is of low molecular weight and can be sufficiently sprayed without preheating, exhibiting excellent adhesiveness with primer. Polyolefin 3 is then sprayed on the polyolefin 2 to form a film 2mm or more in thickness. The polyolefin 3 has adhesiveness of MI<=5 and when it is flame-sprayed, the polyolefin 2 is melted again due to the heat of flame spray of the polyolefin 3 to establish sufficient adhesive force between both the polyolefins. Since the polyolefin 2 ensures adhesive force with the steel material and the polyolefin 3 maintains the property of material, they have sufficient performance as anti-corrosion coating. |
