JB/T 5067-1999 This standard is a revision of JB/T 5067-91 "Mechanical zinc coating of steel parts by powder coating" which is not equivalent to BS 4921-88 of the United Kingdom. The main differences between this standard and BS 4921 are as follows: ——BS 4921 only divides the zinc coating into two grades, while this standard divides it into five grades; ——BS 4921 puts forward the requirement of reserved clearance for zinc coating of thread, while this standard does not make such requirement. Compared with JB/T 5067-91, the main technical content of this standard has been changed as follows: ——The name has been changed and a strict and accurate definition has been given; ——The zinc coating thickness grades have been reclassified; ——Phosphating and organic coating have been added to the post-treatment; ——Corrosion resistance test requirements have been cancelled; ——The original standard's adhesion strength test adopts the hammer method and is changed to be negotiated between the supply and demand parties. This standard specifies the technical requirements and test methods for zinc coating of steel parts by powder coating. This standard is applicable to the zinc coating of parts and components made of carbon steel, low alloy steel, cast iron and other materials. This standard is not applicable to the zinc plating of steel parts that need to be tempered at a temperature below 340℃ to meet the mechanical property requirements of the parts. JB/T 5067-1999 Powder zinc plating of steel parts JB/T5067-1999 Standard download decompression password: www.bzxz.net
JB/T 5067-1999 This standard is not equivalent to the British BS 4921-88, which is a revision of JB/T 5067-91 "Mechanical zinc plating of steel parts by powder". There are the following main differences between this standard and BS 4921: - BS 4921 only divides the zinc plating layer into two grades, while this standard divides it into five grades; - BS 4921 puts forward the requirement of reserved clearance for thread zinc plating, while this standard does not make such requirement. Compared with JB/T 5067-91, the main technical content of this standard has changed as follows: - The name has been changed and a strict and accurate definition has been given; - The thickness grades of the galvanizing layer have been reclassified; - Two types of post-treatment, phosphating and organic coating, have been added; - The corrosion resistance test requirements have been cancelled; - The adhesion strength test of the original standard has been changed from the hammer method to the negotiation between the supply and demand parties. This standard specifies the technical requirements and test methods for powder galvanizing of steel parts. This standard is applicable to the galvanizing of parts and components made of carbon steel, low alloy steel, cast iron and other materials. This standard is not applicable to the galvanizing of steel parts that need to be tempered at a temperature below 340°C to meet the mechanical property requirements of the parts.

ICS25.220.20
Machinery Industry Standard of the People's Republic of China
JB/T5067-1999
Sherardizing of ironand steelarticles
Issued on 1999-06-28
State Bureau of Machinery Industry
Implementation on 2000-01-01
JB/T5067-1999
This standard adopts the British BS4921-88 "Sherardizing of Iron and Steel Powder" and revises JB/T506791 "Sherardizing of Iron and Steel Articles by Mechanical Powder".
This standard has the following main differences with BS4921: In this standard, the zinc-diffusion layer is divided into five grades according to the thickness of the zinc-diffusion layer, while BS4921 only divides it into two grades; DS4921 puts forward the requirement of reserved gap for the zinc-diffusion of threaded parts, while this standard requires the same. Compared with JB/T5067-91, the main technical content of this standard has changed as follows: - The original standard name "powder mechanical galvanizing of steel parts" has been changed to "powder zinc-diffusion of steel parts", and a strict and accurate definition has been given;
This standard has reclassified the zinc-diffusion layer thickness grades: the post-treatment of the first standard has added two types, phosphating and organic coating; this standard has cancelled the corrosion resistance test requirements; - The adhesion strength test of the original standard adopts the hammer method, while this standard has changed to the negotiation between the supply and demand parties. This standard replaces JB/T5067-91 from the date of implementation. Appendix A of this standard is a prompt appendix.
This standard is proposed and managed by the National Technical Committee for Standardization of Metallic and Non-metallic Coverings. The responsible drafting unit of this standard: Wuhan Institute of Material Protection. The drafting unit of this standard is Henan Power Transmission and Transformation Construction Company. The main drafters of this standard are Wu Yong, Li Chunyan and Wang Cheng. 1 Scope
Mechanical Industry Standard of the People's Republic of Chinabzxz.net
Sherardizing of iron and steel articles
Sherardizing of iron and steel articles This standard specifies the technical requirements and test methods for powder shearing of iron and steel articles (hereinafter referred to as shearing). This standard applies to shearing of parts and components made of carbon steel, low alloy steel, cast iron and other materials. JB/T5067-1999
Replaces JB/T5067-91
This standard does not apply to shearing of steel articles that require tempering treatment at a temperature below 340℃ to meet the mechanical property requirements of the parts. 2 Referenced Standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and parties using this standard should explore the possibility of using the latest versions of the following standards. GB/T4956——1985
GB/T13825—1992
JB/T50691991
3 Definitions
3.1 Powder sherardizing
Measurement of the thickness of non-magnetic coating on magnetic metal substrate Magnetic method Metal coating Determination of the mass of hot-dip galvanized layer of ferrous metal material Weighing method Metallographic inspection method of infiltrated metal layer of steel parts Surface treatment process that uses powder sherardizing agent as zinc source and forms a sherardizing layer on the steel surface by heating to produce mutual diffusion of zinc and iron atoms.
3.2 Sherardizing layer
Zinc-iron alloy layer formed on the steel surface by mutual diffusion of zinc and iron atoms. 3.3 Sherardizing agent
A sherardizing agent composed of a zinc supply component containing zinc atoms, and with or without the addition of filling components, activation components, etc. as required. 4 Information that the demander should provide to the supplier
a) This standard number;
b) Material brand of the workpiece to be infiltrated:
c) Thermal processing system of the workpiece to be infiltrated;
d) The required thickness of the zinc layer of the workpiece to be infiltrated;
e) Whether post-treatment is required after the zinc infiltration and what kind of post-treatment is used. 5 Technical requirements
5.1 Workpiece to be infiltrated
5.1.1 The mechanical properties of the material of the workpiece to be infiltrated can still meet the requirements of the original design indicators after the zinc infiltration heating process. Approved by the State Machinery Industry Bureau on June 28, 1999, and implemented on January 1, 2000
JB/T5067-1999
5.1.2 The surface of the workpiece to be infiltrated should be free of residual welding slag, molding sand, carbon deposits and serious oil pollution. 5.2 Appearance
a) The surface of the sherardizing layer should be flat and uniform by visual inspection, and slight scratches are allowed. The uneven surface of the sherardizing layer caused by sand holes, slag inclusions, etc. in the infiltrated part itself should not be regarded as an appearance defect: b) The sherardizing layer is gray or silver gray;
c) The sherardizing parts treated by passivation, phosphating and organic coating have different colors due to different processes. 5.3 Adhesion strength
The sherardizing layer should be well bonded to the substrate, without peeling or falling off, and can withstand the operation under the standard conditions of the part, or negotiated by the supply and demand parties.
5.4 Thickness
The sherardizing layer should be uniform, and the thickness deviation of the sherardizing layer of the same part should not be greater than 10% of the average thickness of the sherardizing layer of the part. According to the different use environments and matching requirements of the parts, the sherardizing layer is divided into five levels, and the thickness of each level of the sherardizing layer should meet the requirements of Table 1.
Galvanizing layer thickness grade
Thickness μm
Note: Under given conditions, the corrosion resistance life of the galvanizing layer is proportional to its thickness. However, while increasing the thickness of the galvanizing layer, the geometric dimensions of the parts are also increased, so the matching requirements of the parts should also be considered while considering the life. For the selection of galvanizing layer thickness for fasteners and other parts (recommendations), see Appendix A (suggestive appendix).
5.5 Post-treatment of galvanizing
5.5.1 After galvanizing, polishing, passivation, phosphating, organic coating and other post-treatments can be selected to improve the appearance of the galvanized parts or further improve the corrosion resistance of the galvanizing layer.
5.5.2 When chemical polishing, passivation and phosphating are used as post-treatments after galvanizing high-strength steel parts, whether it is necessary to perform heat treatment to eliminate hydrogen embrittlement and what kind of heat treatment process conditions to use to eliminate hydrogen embrittlement shall be negotiated by the supply and demand parties. 6 Sampling
Two samples should be taken from each batch of sherardized parts. If any of the samples does not meet the technical requirements, the sampling shall be doubled and then inspected. If any of the samples still does not meet the requirements, the batch of products shall be deemed unqualified. 7 Inspection method
7.1 Appearance
Observe with the naked eye under natural scattered light. 7.2 Thickness
7.2.1 Microscope measurement method
The microscope measurement method is the arbitration method for the thickness of the shear layer, and the inspection shall be carried out in accordance with the provisions of JB/T5069. 7.2.2 Dissolution weighing method
The result obtained by the dissolution weighing method is the average mass of the shear layer per unit area on the surface of the steel workpiece, and the inspection shall be carried out in accordance with the provisions of GB/T138252
JB/T50671999
. The average mass of the zinc-diffused layer per unit area can be approximately converted into the thickness of the zinc-diffused layer according to 1g/m2 corresponding to 0.14μm layer thickness. 7.2.3 Magnetic Thickness Gauge Method
The magnetic thickness gauge method is mainly used for production control. Inspection shall be carried out in accordance with the provisions of GB/T4956. JB/T5067-1999
Appendix A
(Suggested Appendix)
Selection of the thickness of the zinc-diffused layer
When selecting the thickness of the zinc-diffused layer, it is necessary to consider both the service life of the zinc-diffused layer in different corrosive environments and the matching requirements. For fasteners and other products of different use environments and different specifications, the following zinc-diffused layer thickness grades are recommended. Table A1
Recommended sherardizing layer thickness grade
Sherardizing layer thickness grade
Grade 4, Grade 5
Use environment and parts
Fasteners and other steel parts used indoors and in rural atmospheric environmentsFasteners and other steel parts used outdoors that require a longer corrosion resistance life than Grade 2 and that can meet the matching requirements after sherardizingFasteners and other parts with special requirements
Fasteners with a nominal size of 1mm and 2mm may be difficult to screw even with Grade 1 sherardizing. It is recommended to use other processes that can obtain a thinner galvanized layer.
2 Parts with special requirements refer to those that require the longest possible corrosion resistance life and have no matching requirements or reserved gaps in the zinc layer before zincizing: People's Republic of China
Mechanical Industry Standard
Powder zincizing of steel parts
JB/T5067-1999
Published and distributed by the Machinery Standardization Research Institute of the Ministry of Machinery Industry Printed by the Machinery Standardization Research Institute of the Ministry of Machinery Industry (No. 2 Shouti South Road, Beijing
Format 880×1230
First edition in July 1999
Printing 1-500
Postal code 100044)
Sheet 1/2
Word count 10,000
First printing in July 1999
Price 5.00 yuan
99-014
6661900
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