12

2023

-

09

What defects often occur during the metal powder metallurgy compaction process?

Author:


During the metal powder metallurgy pressing process, compact defects may occur due to various reasons, resulting in powder metallurgy parts being scrapped. So, what defects often occur during the metal powder metallurgy compacting process?

1. The compact density does not meet the design requirements

In the production of metal powder metallurgy parts, the higher the density of the material, the higher its physical and mechanical properties. In other words, the density and distribution of the compacted metal powder metallurgy parts will determine the performance of the product. Therefore, during the debugging and pressing process of metal powder metallurgy molds, the density of the compact is an item that must be tested. During density testing, it should be noted that compacts with different structures and requirements should be treated differently.

2. The size of the compact does not meet the requirements

2.1 Unqualified radial size or unqualified hole spacing

There may be a problem with the mold design or manufacturing. If the error can be eliminated by adjusting the process (that is, by adjusting the powder composition, compact density, sintering process, etc.). It can also be remedied, otherwise the mold will only be scrapped.

2.2 Unqualified axial dimensions

For stepless cylindrical compacts, the axial size can be adjusted and stabilized by adjusting the powder loading, changing the pressing pressure or extending the holding time. For step compacts, the step height can be changed by adjusting the forming position of the combined die punch, the powder loading ratio of each station, and the operating speed of the floating die punch.

3. Geometric tolerance is out of tolerance

3.1 Straightness

Reasons for excessive straightness include: excessive straightness of the mold, uneven density distribution of the compact, uneven wall thickness of the compact, etc.

3.2 Parallelism

Reasons for excessive parallelism include: excessive parallelism of the mold, uneven powder loading, etc.

3.3 Coaxiality

Reasons for excessive coaxiality include: excessive mold accuracy, low accuracy of pressing tooling and equipment, mold installation that does not meet requirements, uneven decoration, etc.

When the powder flow rate is appropriate, the mold accuracy meets the design requirements, and the pressing tooling and equipment accuracy meets the installation requirements, the geometric tolerance is mainly related to the density distribution of the compact. When the pressing method is determined, the density distribution of the compact is directly related to It is related to the powder filling effect.

4. Unsatisfactory appearance

High roughness, excessive burrs, dropped edges, rough edges, cracks, etc. are all common appearance defects of the compact.

The above is an introduction to the defects produced during the metal powder metallurgy compaction process. There are many defects in metal powder metallurgy compactions, but the hard-to-find defects that can cause the product to be scrapped are: uneven density and compaction cracks, so everyone must pay attention.

13

2020-03

MIM products usually have the following characteristics

The most suitable wall thickness for MIM is no more than 6mm. Thicker outer wall is acceptable, but the cost will be increased due to the longer processing time and extra material used. In addition, u

20

2020-01

What is the density and strength of MIM products?

The density of a typical MIM is theoretically higher than 98%. Specific density characteristics depend on the choice of material, but it is very close to precision materials.

20

2020-01

19

2018-06

Metal injection molding technology in detail

Metal injection molding (referred to as MIM) is a technology combining powder metallurgy and injection molding, which breaks through the traditional powder metallurgy product shape and strength limitations, also breaks through the strength limitations of die casting, breaks through the material flow restrictions of stamping molds, and breaks through precision. Mass production restrictions for casting and high cost constraints for turned parts.

19

2018-06

The market competition pattern of 3D printed metal powder may change

The market competition pattern of 3D printing metal powder will change as more companies enter or increase their production and R & D efforts in the field of metal powder. In 2016, GKN, Oerlikon and Alcoa made active strategic plans.

09

2017-09

Rich variety of raw materials, and the variety of domestic powder metallurgy products has been expanded

In terms of raw materials, at present, the main raw materials of powder metallurgy in China are not only reduced iron powder, electrolytic copper powder, etc., and domestic production of atomized iron powder, stainless steel powder, high-speed steel powder, coated powder and various element metal MIM powder, Ceramic powders can basically meet the needs of domestic production of high-strength parts, and can also produce raw material powders for special purposes, which greatly expands the variety of powder metallurgy products, but there is still a large gap in quality and variety from abroad.

Huizhou Yonglixing Industrial Co., Ltd.

Address: Laohuling Industrial Park, Xiaojinkou Town, Huicheng District, Huizhou City, Guangdong Province
Telephone: 86-752-7823176
Mobile: 86-138 2998 5513
Fax: 86-752-7823172
E-Mail: martin@wotta.net

 

【日本·兵庫】
 (株)ジョイトジャパン JOITO JAPAN CO.,LTD.
 ADD: 兵庫県神戸市中央区磯部通-1-20
 TEL: 81-050-6865-5905


Copyright©Huizhou Yonglixing Industrial Co., Ltd. All Rights Reserved