JP3946370B2 - Steel loom parts - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to flat healds, droppers, wings, deformed rods and the like which are easily worn by contact with fibers. The present invention relates to a loom member such as a lead.
[0002]
[Prior art and problems]
Flat heald, dropper, cocoon feather, deformed cocoon. A structure reinforcing material obtained by quenching stainless steel SUS420J2 is used for a loom member such as a lead. In this type of loom member, the wear environment has become severe with the improvement of the material quality of the fibers used in the woven fabric and the increase in the speed for improving the production efficiency. As a result, the service life of the parts is reduced, and complicated replacement of repair parts is unavoidable.
[0003]
[Problems to be solved by the invention]
The present invention has been devised to solve such a problem. By dispersing hard titanium carbide and niobium carbide in a matrix, the present invention exhibits sufficient wear resistance even in a severe wear environment. It aims at providing the steel loom member used over a period.
[0004]
[Means for Solving the Problems]
In order to achieve the object of the steel loom member of the present invention, Cr: 8.0 to 35.0 mass%, C: 0.05 to 1.20 mass%, Si: 1.0 mass% or less, Mn : 1.0 mass% or less, Ti: 0.05 to 1.0 mass% alone, Nb: 0.05 to 1.50 mass% alone, or Ti + Nb: 0.05 to 2.0 mass% in total The remaining Fe and the inevitable impurities are included, and Ti and / or Nb carbides are dispersed and precipitated in the matrix in a total precipitation amount of 0.1% by mass or more.
[0005]
[Action]
The present inventors gathered a large number of worn-out loom members and fibers actually used, and investigated the wear-damaged sites and fibers from a microscopic viewpoint. As a result, in most of the worn members, wrinkles that were ground into thin lines were observed in the worn portions. Moreover, adhesion of hard particles such as alumina and silicon carbide was detected on the used fibers. From the adhesion of wrinkles and hard particles that were ground, it was found that the wear phenomenon at this time was wear mediated by hard particles. In the present specification, wear in which hard particles are present on the contact surface between the fiber and the loom member and the contact surface of the loom member is abraded or ground by the hard particles in the vibration or sliding process is referred to as abrasive wear.
[0006]
Abrasive wear is the most severe of various wear phenomena, and the development of materials that can withstand this wear is desired.
As a method of improving the wear resistance, a method of increasing the strength by quenching a steel material having an increased carbon content was examined. As the quenching hardness increases, the amount of abrasive wear decreases slightly, but no significant wear-inhibiting effect is exhibited, and it has been found that the wear resistance cannot be significantly improved by strengthening the structure by adding carbon. The material hardened by cold working could not improve the wear resistance like the structure reinforcing material.
[0007]
The fact that the resistance to abrasive wear cannot be increased by strengthening the structure or strengthening the work is due to the fact that the hard particles such as alumina and silicon carbide are very hard and harder than the hardness obtained by strengthening the structure and hardening the work. Inferred to be. That is, the hardness obtained by structure strengthening, work hardening, and the like is very small compared to the hardness of hard particles such as alumina and silicon carbide, and is considered to have little action to suppress abrasive wear.
[0008]
In the process of elucidating the wear mechanism and investigating materials that can withstand wear, it was found that when hard carbide is dispersed and precipitated in a steel matrix in a predetermined amount or more, the wear resistance is dramatically improved. Specifically, attention was paid to Ti and Nb carbides as carbides having almost the same hardness as hard particles such as alumina and silicon carbide, and the relationship between the amount of precipitation of these carbides and wear resistance against abrasive wear was investigated. As a result, it was found that even if the material has the same hardness, the abrasive wear is effectively suppressed when the carbides of Ti and Nb are dispersed and precipitated.
[0009]
The steel material which this invention makes object contains 8.0-35.0 mass% Cr in order to provide corrosion resistance. When the Cr content is less than 8.0% by mass, the anticorrosion effect due to the addition of Cr is reduced. However, when an excessive amount of Cr exceeding 35.0% by mass is included, the hot workability is lowered, and the manufacturing cost is increased.
[0010]
Ti and / or Nb are Ti: 0.05 to 1.0% by mass independently, and Nb: 0.05 to 1.50% by mass so that the total precipitation amount of carbide is 0.1% by mass or more. Or Ti + Nb: It adds in the ratio of 0.05-2.0 mass% in total amount. The total carbide precipitation amount of 0.1% by mass or more is a critical value found from the investigation of the influence of precipitated carbides on wear resistance, as described in the examples described later, and is 0.1% by mass or more. By ensuring the total amount of precipitation, it is possible to obtain much superior wear resistance compared to steel materials without carbides. When set to Ti: 0.05% by mass or more, Nb: 0.05% by mass or more, or Ti + Nb: 0.05% by mass or more, the total amount of carbides dispersed and precipitated in the matrix becomes 0.1% by mass or more. . However, if Ti is added excessively, the hot water flow during melt casting is deteriorated. If Nb is added excessively, it precipitates as an intermetallic compound and lowers toughness. Therefore, the upper limit of Ti content is 1.0 mass%, Nb The upper limit of the content was set to 1.50 mass%, and the upper limit of the Ti + Nb total content was set to 2.0 mass%.
[0011]
In order to make the total precipitation amount of carbides 0.1% by mass or more, 0.05% by mass or more of carbon is contained. Carbon is an alloy component that is not only consumed in the formation of carbides but also effective in strengthening the structure. However, if the C content exceeds 1.20% by mass, a large amount of eutectic chromium carbide is precipitated in a large amount, resulting in deterioration of quality, hot workability and the like.
[0012]
Other alloy components include Si: 1.0 mass% or less and Mn: 1.0 mass% or less. Si is a component added as a deoxidizing / reducing agent at the time of melting, but an excessive amount exceeding 1.0% by mass lowers the toughness of the steel material. Mn is also a component added as a deoxidizing / reducing agent during melting, but if it exceeds 1.0% by mass, retained austenite increases at the time of quenching, which causes a decrease in the hardness and toughness of the steel material.
[0013]
【Example】
Various steels shown in Table 1 were melted in accordance with conventional methods and cast into slabs. After the solution treatment, the slab was hot rolled to a thickness of 5 mm. The hot-rolled sheet was heat-treated at 780 ° C. for 9 hours and cooled in the furnace. After pickling the hot-rolled annealed plate, cold rolling and annealing were repeated to produce a cold-rolled annealed plate having a thickness of 0.30 mm.
[0014]
[0015]
A specimen for wear test was cut out from the obtained cold-rolled annealed plate, processed into a flood heald for a loom member, heated and maintained at 1050 ° C. for 1 minute in a non-oxidizing atmosphere furnace, and then air-cooled to room temperature. The carbides dispersed and precipitated on the specimen were quantitatively analyzed, and the wear resistance and corrosion resistance against abrasive wear were investigated.
The amount of carbide precipitation was determined from the amount of carbide residue remaining in the solution after immersing a test piece in which the amount of carbide was controlled by solid solution / precipitation treatment in an iodine alcohol solution and applying ultrasonic to dissolve the steel. . The form of carbide was identified by X-ray diffraction of the residue, and the amount of each metal element was determined by wet analysis and gas analysis.
[0016]
In the abrasion resistance test, chemical fiber (TFD75 / 36F, fiber diameter 120 μm) was passed through the mail hole of the test piece flood-held, fiber tension: 50 g, rotation speed: 800 rpm (sliding speed: 0.1 m / second), Test time: Contact sliding was performed under the condition of 10 hours, and the wear depth of the contact portion was measured. Then, the amount of wear of the mail part worn by contact with the fiber is obtained and calculated as the ratio of the wear depth D _i of each test piece to the wear depth D ₀ with reference to the wear depth D ₀ of stainless steel SUS420J2. Abrasion resistance was evaluated using the following index M (%) (= D _i / D ₀ × 100). In order to obtain wear characteristics more than twice that of the currently used stainless steel SUS420J2 flooded heald, M ≦ 50% wear resistance is required.
Regarding the corrosion resistance, the test piece was subjected to a test in which 5% salt water was sprayed for 72 hours, and then the surface of the test piece was observed to examine whether or not rust was generated.
[0017]
As can be seen from the results of the investigation in Table 2, rust was observed on the surface of the test piece for test number 8 with a Cr content of less than 8% by mass, but for any other steel type containing 8% by mass or more of Cr, any test piece No rust was detected on the surface. From this, it can be seen that 8% by mass or more of Cr is necessary to ensure corrosion resistance. In Test Nos. 8 to 10 in which the total precipitation amount of titanium carbide and niobium carbide is less than 0.1% by mass, the index M is not greatly reduced as compared with Test No. 11 (conventional material). On the other hand, in test numbers 1 to 7 (examples of the present invention) in which the total precipitation amount is 0.1% by mass or more, the index M is less than 30%, which is more than three times the life of the conventional flooded. It turns out that it has.
[0018]
Therefore, when the index M and the total precipitation amount of titanium carbide and niobium carbide are graphed, the relationship shown in FIG. 1 is established between the two. As is clear from FIG. 1, the index M decreased as the total precipitation amount of carbides increased, and the index M decreased rapidly when the total precipitation amount became 0.1 mass% or more. When the total precipitation amount of carbide was adjusted to 0.1% by mass or more, the index MC was reduced to 50% or less, and it was found that a flood heald having a lifetime of twice or more that of the conventional material was obtained.
[0019]
[0020]
【The invention's effect】
As described above, the steel of the present invention is composed of Ti and / or Nb carbides having substantially the same hardness as hard particles such as alumina and silicon carbide that cause abrasive wear. By dispersing and precipitating in the matrix at a ratio, a much superior wear resistance is imparted compared to a structure reinforcing material by quenching or a processing reinforcing material by cold working or the like. Therefore, it is used as a loom member having a long life, such as a flood heald, a dropper, a kite feather, a deformed kite, and a lead that wears in contact with fibers.
[Brief description of the drawings]
FIG. 1 is a graph showing the effect of the total precipitation amount of titanium carbide and niobium carbide on wear resistance.

Claims (1)

Cr: 8.0 to 35.0 mass %, C: 0.05 to 1.20 mass %, Si: 1.0 mass % or less, Mn: 1.0 mass % or less, Ti: 0.05 to 1.5% alone 1.0% by mass , Nb: 0.05 to 1.50% by mass alone or Ti + Nb: 0.05 to 2.0% by mass in total, with the balance of Fe and inevitable impurities , Ti and A steel loom member excellent in fiber wear resistance and corrosion resistance in which Nb carbides are dispersed and precipitated in a matrix in a total precipitation amount of 0.1% by mass or more.