New Nano-Functional Ceramic Coating Technology for High Temperature Protection of Billets

1.

New Nano-Functional Ceramic Coating Technology
for High Temperature Protection of Billets
The pioneer and leader of high-efficiency low-cost billet high
temperature protection technology

2.

Contents
• 01 Oxidation burning loss of billet
• 02 High temperature protection technology
• 03 Technical effect
• 04 Economic benefit

3.

01
Oxidation burning loss of billet

4.

The Oxidation burning loss during billet (ingot) heating process

5.

Adverse effects of high temperature oxidation
During the heating process of rolling steel, the oxidation burning
loss accounts for about 1-1.5% of the weight of the blank.
The forging heating burning loss will be higher, and the burning
loss rate is as high as 3-5%.

6.

Adverse effects of high temperature oxidation
When the furnace gas or furnace temperature is improperly
controlled or the billet stays in the high temperature section for a
long time, especially if the rolling failure occurs and the adjustment
is not timely, the iron oxide scale of the steel will be thickened.
In general, the iron oxide scale thickness is 1-5mm, and in severe
cases, it can reach 10mm.

7.

Adverse effects of high temperature oxidation
If the iron oxide scale produced by high temperature oxidation is
not cleaned up in time, it will be pressed into the surface of the billet
during the rolling or forging process, resulting in surface defects of
the product, causing the product to be scrapped.

8.

Adverse effects of high temperature oxidation
When heating steel parts, high temperature oxidation will cause
depletion and decarburization of alloying elements in the steel.

9.

Adverse effects of high temperature oxidation
The changes in the chemical composition of the steel surface will
cause a decline in the mechanical properties and corrosion
resistance of the product, resulting in a reduction in the qualified
rate of finished products.

10.

Adverse effects of high temperature oxidation
Oxidative burn loss leads to lower yield and higher cost;
Roll printing;
Depletion of surface alloying elements, decarburization;
Secondary Oxidation Thickness/Integrity;
Deterioration of mechanical properties and corrosion resistance;
Surface segregation;
The descaling performance is poor, the qualified rate of the Edge crack;
finished product is reduced, and the precision die forging cannot
be carried out;
Oxide intrusion;
A series of surface quality problems, defects;
Oxygen spot, residual oxygen;
Increased production process and energy consumption;
Copper brittle;
The iron oxide scale corrodes the furnace body, affecting the life Increased pickling costs;
of the furnace body and increasing the heavy manual labor;

11.

02 High temperature protection technology

12.

Solution - high temperature anti-oxidation nano-ceramic coating

13.

03
Technical effect

14.

Brief introduction of high temperature anti-oxidation nano-ceramic
coating
The use of high temperature protective coating technology can reduce
the primary oxidation burn loss by more than 90%, greatly improve the
yield of steel in the production process, directly reduce the difficulty of
removing iron oxide scale, alleviate the phenomenon of surface
element depletion, and improve the yield and quality of steel.

15.

Therefore, the research and application of multi-functional hightemperature protective coating technology has more important practical
significance in the aspects of anti-oxidation, anti-decarburization, antielement depletion and improvement of descaling level and rolled surface
quality of high value-added steel grades.

16.

Characteristics of high temperature anti-oxidation nano-ceramic
coating
• 1. The coating can reduce the surface oxidation of the billet by more
than 90%, greatly reducing the element depletion;

17.

Characteristics of high temperature anti-oxidation nano-ceramic
coating
• 2 Good chemical compatibility, mechanical compatibility, and CTE
(coefficient of thermal expansion) matching between the coating and
the substrate and between the inner layer of the coating and the layer;

18.

Characteristics of high temperature anti-oxidation nano-ceramic
coating
• 3. The coating is closely combined with the substrate during the
transmission of the steel, and the mechanical action will not cause the
coating to fall off at high temperature;

19.

Characteristics of high temperature anti-oxidation nano-ceramic
coating
• 4. The existing oxide layer on the surface of the coating and the steel
substrate forms a new dense eutectic, which changes the structure of
the oxide layer and improves the peeling performance of the oxide
scale;

20.

Characteristics of high temperature anti-oxidation nano-ceramic
coating
• 5. The amount of coating is small, which does not affect the normal
heating speed of the billet;

21.

Characteristics of high temperature anti-oxidation nano-ceramic
coating
• 6. The coating can automatically heal the cracks generated by
itself in the high temperature process, ensuring the
compactness and integrity of the coating;

22.

Characteristics of high temperature anti-oxidation nano-ceramic
coating
• 7. The coating itself has anti-oxidation performance and long
protection life;

23.

Characteristics of high temperature anti-oxidation nano-ceramic
coating
• 8. The cost of coating is low. The existing anti-oxidation
coatings for special steels are relatively expensive, while for
ordinary low-carbon steels used in a large number of
applications, these coatings are not practically applied, because
of high cost.

24.

Application effect of high temperature protective coating technology

25.

Forging field application

26.

Dephosphorization of nickel-containing steel hot rolled coils by
protective coatings ---- Surface quality is improved

27.

Mitigation effect of protective coating on decarburization depth of
medium and high carbon steel grades

28.

Mitigation effect of protective coating on decarburization depth of
medium and high carbon steel grades

29.

Mitigation effect of protective coating on the depth of decarburized
layer of bearing steel

30.

Practical significance of applying high temperature protective coating
technology
• Compared with the existing high-temperature protective coatings,
the coating increases the protective temperature, effectively reduces
the high-temperature oxidation burning loss, improves the peeling
performance of the iron oxide scale after it is released from the
furnace, saves energy to a large extent, and improves the yield and
surface quality of the billet, from the perspective of energy saving,
production and efficiency of steel rolling heat treatment production,
it has produced obvious benefits.

31.

Practical significance of applying high temperature protective coating
technology
• Most of the heating furnaces in the rolling and forging industries in
the country are at a relatively low level in the world, which is why
the oxidation burning loss and surface quality of the forging industry
urgently need to be improved.

32.

Practical significance of applying high temperature protective coating
technology
• The improvement of surface quality has played a significant role in
improving the equipment life of downstream processes such as
rolling process, pickling process and other supporting links, and
reducing material consumption.

33.

Practical significance of applying high temperature protective coating
technology
• The improvement of product quality also increases the added value
of products and enhances the strategic competitiveness of enterprises
themselves.

34.

How to use high temperature protective coating
Coating Method
Air spray
Coated Weight
Maintenance after Application
Below 1000 ° C standard coated
weight is 150g/m2
Rolled steel billets can be sprayed
online and dried using the waiting
1100° C -1150° C, standard coated time and temperature before
weight is 200g/m2
entering the furnace.
coating by brush, roller brush
1150-1200° C, standard
weight is 250g/m2
High-pressure airless spraying
Immersion
coated
Forging blanks can be cured for
10 hours to achieve the best use
1200-1300° C standard coated effect.
weight is 350g/m2
Under different steel grades and
different heating systems, the use
effect will be different, and the use
amount must be determined
according to the field test.

35.

04
Economic benefit

36.

Calculation of technical economic benefit of applied high
temperature protective coating
5 million tons of ordinary carbon steel rolling mill as an example
• 1. Oxidation and burning condition:
The firing temperature is about 1200℃-1260℃, and the average
oxidation burning loss rate of the billet is about 1.20%. The annual
steel billet oxidation and burning loss is 60,000 tons, and the direct
economic loss is: 60,000 tons × 3,800 / ton = 228 million RMB.

37.

Calculation of technical economic benefit of applied high
temperature protective coating
• 2. Saving benefits:
After using our company's high-temperature anti-oxidation coating, the target is
to reduce the oxidation burning loss rate by more than 80%, which can save the
company 48,000 tons of steel billets every year, equivalent to 182 million RMB,
and the coating consumption is about 0.8kg/ton, 4000t/year, The coating price is
15 RMB/kg, the coating cost is 60 million yuan, and the iron and steel enterprises
can obtain direct economic benefits of 120 million RMB. At the same time, it
brings the improvement of product surface quality, improves the product
qualification rate, and the indirect benefits are also very considerable !
For special steel, alloying elements such as Si Ni Mn have complex reactions.
Our company produces special coating materials for different steel grades.

38.

Strive to create more value for target customers