Metal strip product

Abstract

A coated steel strip product with a dense and hard abrasion resistant coating on one side or both sides of said strip substrate is provided. The thickness of said coating is in total maximally 25 μm, the hardness of said coating is at least 600 HV and the tensile strength of the steel strip substrate is at least 1200 MPa. The coating is preferably applied by electron beam evaporation and the coating may be, e.g., of Al 2 O 3 . The coated metal strip is suitable for shaving equipment, medical instruments, utility and industrial knives as well as saw applications.

1 . A coated steel strip product, comprising: 
 a steel strip substrate; and    a dense and hard abrasion resistant coating on one side or both sides of said strip substrate, the coating including at least one layer of an oxide and at least one layer of a transition metal nitride or a transition metal carbide,    wherein the coating is directly applied on the strip substrate, a thickness of the coating is in total maximally 25 μm.    
   
   
       2 . The product according to  claim 1 , wherein a ratio between the thickness of the coating and a thickness of the strip substrate is 0.001 to 7%.  
   
   
       3 . The product according to  claim 1 , wherein the oxide is Al 2 O 3 , TiO 2 , ZrO 2 , or a mixed oxide based on Al 2 O 3 , TiO 2 , or ZrO 2 .  
   
   
       4 . The product according to  claim 1 , wherein a hardness of the coating is at least 600 HV and a tensile strength of the steel strip substrate is at least 1200 MPa.  
   
   
       5 . The product according to  claim 1 , wherein the thickness of the strip substrate is between 0.015 mm and 5.0 mm.  
   
   
       6 . The product according to  claim 1 , wherein the strip substrate is made of hardenable carbon steel, hardenable stainless chromium steel, or precipitation hardenable strip steel.  
   
   
       7 . The product according to  claim 1 , wherein the coating is a mixture including Al 2 O 3  and ZrO 2  and the mixture has a main ingredient of Al 2 O 3 .  
   
   
       8 . The product according to  claim 7 , wherein the mixture includes TiO 2 .  
   
   
       9 . The product according to  claim 1 , wherein the coating is a metallic coating including Cr.  
   
   
       10 . The product according to  claim 1 , wherein the coating has a multi-layer structure of a plurality of individual layers.  
   
   
       11 . The product according to  claim 10 , wherein the coating has a multi-layer structure of up to 10 layers.  
   
   
       12 . The product according to  claim 10 , wherein each individual layer of the multi-layer structure has a thickness of between 0.1 to 15 μm.  
   
   
       13 . The product according to  claim 10 , wherein the individual layers include Al 2 O 3  and ZrO 2 .  
   
   
       14 . The product according to  claim 13 , wherein the individual layers include TiO 2 .  
   
   
       15 . The product according to  claim 13 , wherein individual layers include nitrides or carbides.  
   
   
       16 . The product according to  claim 15 , wherein the nitrides include TiN and the carbides include TiC.  
   
   
       17 . The product according to  claim 15 , wherein individual layers of the multi-layer structure include a metallic coating.  
   
   
       18 . The product according to  claim 17 , wherein the metallic coating consists essentially of Cr.  
   
   
       19 . The product according to  claim 1 , comprising at least one layer of nickel having a thickness up to 2 μm, the at least one layer not adjacent the strip substrate.  
   
   
       20 . The product according to  claim 1 , wherein the coating includes transition metal carbides, transition metal nitrides or mixtures thereof.  
   
   
       21 . The product according to  claim 20 , wherein the coating includes TiN, TiC, CrN, or mixtures thereof.  
   
   
       22 . The product according to  claim 1 , wherein the ratio between the thickness of the coating and the thickness of the strip substrate is 0.01 to 7%.  
   
   
       23 . The product according to  claim 22 , wherein the ratio is 0.01 to 5%.  
   
   
       24 . A shaving product, including the coated steel strip product as in any one of claims  1 ,  7 ,  11  and  19 .  
   
   
       25 . The shaving product of  claim 24 , wherein the shaving product is a razor blade.  
   
   
       26 . A knife including the coated steel strip product as in any one of claims  1 ,  7 ,  11  and  19 .  
   
   
       27 . The knife of  claim 26 , wherein the knife is a utility knife, an industrial knife, or a surgical knife.  
   
   
       28 . A saw including the coated steel strip product as in any one of claims  1 ,  7 ,  11  and  19 .  
   
   
       29 . The saw according to  claim 28 , wherein the saw is a hand saw or an industrial saw.  
   
   
       30 . A method of manufacturing a coated steel strip product, the coated steel strip product having a steel strip substrate and a dense and hard abrasion resistant coating on one side or both sides of said strip substrate, wherein the coating includes at least one layer of an oxide and at least one layer of a transition metal nitride or a transition metal carbide, the coating is directly applied on the strip substrate, a thickness of the coating is in total maximally 25 μm, and a ratio between the thickness of the coating and a thickness of the strip substrate is 0.001 to 7%, the method comprising: 
 operating a strip production line in a continuous roll-to-roll process at a feed rate of at least 2.5 m/min to feed the strip substrate;    removing a native thin oxide layer from the strip substrate by ion assisted etching in an etch chamber to form a cleaned strip substrate; and    depositing the coating directly on the cleaned strip substrate by a physical vapor deposition technique in a deposition chamber,    wherein both the etch chamber and the deposition chamber are integrated into the continuous roll-to-roll process.    
   
   
       31 . The method according to  claim 30 , wherein a hardness of the coating is at least 600 HV and a tensile strength of the steel strip substrate is at least 1200 MPa  
   
   
       32 . The method according to  claim 30 , comprising forming the coated strip substrate into a final dimension by slitting or edge treatment.  
   
   
       33 . The method according to  claim 30 , wherein the coating is a multi-layer coating and the method comprises forming the multi-layer coating by a plurality of depositions by the physical vapor deposition technique.  
   
   
       34 . The method according to  claim 30 , wherein the physical vapor deposition technique is electron beam evaporation in an electron beam deposition chamber.  
   
   
       35 . The method according to  claim 34 , wherein electron beam evaporation is plasma activated.