JPS6032708B2 - Fe-based sintered alloy with high strength and toughness - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to the production of Fe, which has high strength and toughness and can be manufactured at a lower sintering temperature than the conventional sintering temperature.
This is related to the Akatsuki Coupling.

Conventionally, in the production of mechanical structural parts, F as specified in Types 2 to 5 of the Japan Powder Metallurgy Association Standards (JPNA) has been used.
E-based sintered alloys are used, and these competitive Fe-based alloys are made by blending Fe powder as a starting raw material powder with C powder, Cu powder, or Ni powder as an alloying component.
The powder is mixed and formed into a compact at a pressure of about 5 n', and then the compact is heated in a non-oxidizing atmosphere at a temperature of 1120 to 1
It is manufactured by heating and holding at 150 qo for a predetermined time and solidifying, and the resulting alloy has a
Tensile strength of 0k9' or more, elongation of 1% or more, and 6
．． It is specified that the density is 2 ta' or more. The present invention is suitable for use in the field of use of the conventional Fe-based sintered alloys, and on the other hand, allows for freezing at a much lower temperature than the conventional Fe-based sintered alloys, and It has properties equal to or better than Akatsuki Metal,
In particular, it provides a new Fe-based sintered alloy that has both high strength and high number properties, expressed in weight% (hereinafter % indicates weight%).
, P:0.05-0.25Mh, Ni, Cu, and S
Contains one or more of n: 0.3 to 2.5%, and if necessary, further contains C: 0.3 to 1%, with the remainder being Fe and unavoidable impurities. The composition is such that the dispersed phase is composed of Fe particles, while the binder phase is
It has a structure composed of an alloy phase in which Fe, P, one or more of Mn, Ni, Cu, and Sn, and further C as a solid solution, and the dispersed phase This is a Fe-based light alloy that is characterized by improved grade properties and improved strength by the binder phase.

Next, the reason why the composition of the Fe-based sintered alloy of the present invention is appropriately limited as described above will be explained. {a' P and
Mn, Ni, Cu, and Sn These components are all components that form a binder phase, and during feeding, they fall into Fe to form a Fe-P-(Mn, Ni, Cu, Sn) alloy,
This has the effect of improving alloy strength, but the content is less than 0.05% P, Mn, Ni, Cu, and Sn.
If the content exceeds 0.25% of P and 2.5% of Mn, Ni, Cu, and Sn, the strength of the binder phase will be reduced. The tendency of F to form a dispersed phase appears.
Since the high toughness brought about by e-grains will be impaired, the content should be adjusted to P: 0.05~
0.25%, one of Mn, Ni, Cu, and Sn
Species or two or more types: 0.3 to 2.5%. [b)
The C component includes the above Fe-P-(Mn, Nj, Cu, S
n) Since it acts as a solid solution in the binder phase consisting of the alloy and further improves the alloy strength, it is included as necessary when even higher strength is required, but the content is 0.
If the content is less than 3%, the desired effect of improving the alloy strength cannot be obtained, while if the content exceeds 1%, the binder phase becomes arms and the ballability of the alloy decreases. The content was determined to be 0.3 to 1%.

In addition, the alloy of this invention "First, P, Mn, Ni, C
A eutectic alloy powder or compound powder with one or more of Sn and U is produced by an atomization method, and then, if necessary, this is ground with a ball mill or the like to obtain a fine powder of about 40 mm or less. Then, these fine powders, Fe powder, and if necessary, carbon powder are blended and mixed to have a predetermined final component composition, formed into a technical powder, and then this powder is made into a sub-chamber. It can be produced by dawning at a temperature lower than the dawning temperature, but in this case, even if the liquid phase generation temperature of the eutectic alloy powder or compound powder is, for example, Mn-7.9%P. 960 pm ○, similarly Ni-11%P: 880qo, Cu-8.4%P: 7
14q0, further Sn-16.4%P (S to P3): 5
At a low temperature such as 50°C, the eutectic alloy powder or compound powder turns into a liquid phase and forms a liquid phase on the surface of the Fe powder.
However, since the freezing temperature is relatively low, it does not completely diffuse into the Fe powder, so P, Mn, and N are concentrated on the surface of the Fe powder.
one or more of i, Cu, and Sn;
Further, C contained as necessary becomes solidified, and as a result, the dispersed phase is composed of Fe grains, while the binder phase is composed of Fe-P-(Mn, Ni, C-Sn) alloy or It has a structure composed of Fe-P-(Mh, Ni, Cu, Sn)-C alloy. Next, the alloy of the present invention will be explained by examples and in comparison with comparative examples.

Examples Starting raw material powders include Fe powder with a particle size of 10 mm or less, carbon powder with a particle size of 25 mm or less, and further produced by an atomization method and pulverized in a ball mill to obtain a fine powder with an average particle size of 10 to 15 mm. Mm-7.9%P powder, Ni-11%P powder, Cu-84%P powder, and S
n-16.4% P powder was prepared, and these raw material powders were blended into the composition shown in Table 1, mixed, and molded into a green compact at a pressure of 5 n/m, and then heated with hydrogen. Alloys 1 to 16 of the present invention and Comparative Alloys 1 to 8 having substantially the same composition as the blended composition were manufactured by holding the alloys at a competitive temperature of 1050 qo for 3 minutes in an atmosphere.

Table 1 Note that Comparative Alloys 1 to 8 all have a content of binder phase forming components outside the range of the present invention.

The resulting invention alloys 1 to 16 and comparative alloy 1
The tensile strength and elongation of samples 1 to 8 were measured and shown in the attached table.

As is clear from the results shown in Table 1, all of the alloys of the present invention have both high strength and high properties, but the content of the binder phase forming component is lower than the range of the present invention. Comparative alloys 1, 3, 5, and 7 have high toughness but extremely low strength, and their ratios are also high and outside the range of the present invention.

Although Nos. 2, 4, 6, and 8 have rice grains, their grain quality is extremely poor, and none of them have both strength and rut resistance.

As mentioned above, the Fe-based late alloy of the present invention has both high strength and high toughness, so when it is used as a mechanical structural component, it can be used for an extremely long period of time, and it can also be used for a short period of time. Since it can be manufactured at high temperatures, it has industrially useful properties such as great manufacturing utility.

Claims (1)

[Claims] 1 P: 0.05 to 0.25%, one or two of Mn, Ni, Cu, and Sn
Species: 0.3 to 2.5%, with the remainder consisting of Fe and unavoidable impurities (wt%), and the dispersed phase is composed of Fe grains, while the binder phase is composed of Fe, P and M
The dispersion liquid improves toughness, while the binder phase improves toughness. An Fe-based sintered alloy having high strength and high toughness, characterized by improved strength. 2 P: 0.05-0.25%, one or two of Mn, Ni, Cu, and Sn
Species or more: 0.3 to 2.5%, further C: 0.3 to 1%, and the remainder is Fe and unavoidable impurities (weight %), and the dispersed phase is It is composed of Fe grains, while the binder phase is Fe, P, Mn, Ni, Cu, and Sn.
It has a structure composed of an alloy phase in which one or more of the above and C are dissolved in solid solution, and the dispersed phase improves toughness, while the binder phase improves strength. An Fe-based sintered alloy having high strength and toughness.