US20120045359A1 - Wear-resistant aluminum alloy extruded material exhibiting excellent fatigue strength and machinability - Google Patents

Wear-resistant aluminum alloy extruded material exhibiting excellent fatigue strength and machinability Download PDF

Info

Publication number
US20120045359A1
US20120045359A1 US13/287,353 US201113287353A US2012045359A1 US 20120045359 A1 US20120045359 A1 US 20120045359A1 US 201113287353 A US201113287353 A US 201113287353A US 2012045359 A1 US2012045359 A1 US 2012045359A1
Authority
US
United States
Prior art keywords
mass
extruded material
aluminum alloy
machinability
content
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US13/287,353
Other languages
English (en)
Inventor
Karin SHIBATA
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Aisin Keikinzoku Co Ltd
Original Assignee
Aisin Keikinzoku Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Aisin Keikinzoku Co Ltd filed Critical Aisin Keikinzoku Co Ltd
Assigned to AISIN KEIKINZOKU CO., LTD. reassignment AISIN KEIKINZOKU CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: Shibata, Karin
Publication of US20120045359A1 publication Critical patent/US20120045359A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C21/00—Alloys based on aluminium
    • C22C21/02—Alloys based on aluminium with silicon as the next major constituent

Definitions

  • the present invention relates to a wear-resistant aluminum alloy extruded material that exhibits excellent fatigue strength in addition to excellent machinability.
  • the aluminum alloy extruded material When using an aluminum alloy extruded material for automotive brake parts and the like, the aluminum alloy extruded material is required to exhibit wear resistance against sliding parts, and may also required to exhibit high cutting (machining) accuracy and high caulking accuracy.
  • a cylinder, a hydraulic circuit groove, and the like are machined when producing an actuator body (ABS body) used for an automotive antilock brake system, an electronic stability control (ESC) body used for an antiskid brake system, and the like, and a caulking seal is provided after assembly.
  • ABS body actuator body
  • ESC electronic stability control
  • an aluminum alloy extruded material used for such applications is required to exhibit strength, wear resistance against sliding parts, machinability that allows processing into a complicated shape, pressure resistance against a hydraulic oil and the like (caulking section), and high fatigue strength against cyclic (repetitive) load.
  • An aluminum alloy extruded material used for such parts is provided with wear resistance and machinability by dispersing Si particles and Fe particles in the metal structure.
  • Such an aluminum alloy extruded material exhibits insufficient fatigue strength.
  • Japanese Patent No. 3886270 discloses a wear-resistant aluminum alloy extruded material that exhibits excellent machinability and corrosion resistance.
  • the aluminum alloy extruded material disclosed in Japanese Patent No. 3886270 exhibits insufficient caulking properties, fatigue strength, and the like.
  • a wear-resistant aluminum alloy extruded material that exhibits excellent fatigue strength and machinability
  • the aluminum alloy extruded material being formed using an aluminum alloy that comprises 3.0 to 8.0 mass % of Si, 0.1 to 0.5 mass % of Mg, 0.01 to 0.5 mass % of Cu, 0.1 to 0.5 mass % of Zr, 0.4 to 0.9 mass % of Fe, 0.01 to 0.5 mass % of Mn, 0.01 to 0.5 mass % of Cr, and 0.01 to 0.1 mass % of Ti, with the balance being Al and unavoidable impurities.
  • FIG. 1 shows the alloy composition of each extruded material that was evaluated.
  • FIG. 2 shows the evaluation results.
  • FIG. 3 shows a comparison between the S-N curve of the extruded product obtained in Example 1 and the S-N curve of the extruded material obtained in Comparative Example 1.
  • FIG. 4 shows examples of a micrograph used to measure the crystal grain size and the Si particle size.
  • FIG. 5 shows examples of a micrograph used to measure the surface recrystallization depth.
  • FIG. 6 shows corrosion resistance evaluation conditions.
  • the present invention may provide a wear-resistant aluminum alloy extruded material that exhibits excellent fatigue strength and excellent machinability.
  • a wear-resistant aluminum alloy extruded material that exhibits excellent fatigue strength and machinability
  • the aluminum alloy extruded material being formed using an aluminum alloy that includes 3.0 to 8.0 mass % of Si, 0.1 to 0.5 mass % of Mg, 0.01 to 0.5 mass % of Cu, 0.1 to 0.5 mass % of Zr, 0.4 to 0.9 mass % of Fe, 0.01 to 0.5 mass % of Mn, 0.01 to 0.5 mass % of Cr, and 0.01 to 0.1 mass % of Ti, with the balance being Al and unavoidable impurities.
  • the inventor of the invention conducted extensive studies, and found that the fatigue strength of the extruded material is not improved to the desired extent by merely refining the crystal grains.
  • the inventor compared the effects of Zr, Mn, and Cr in detail, and found that Si particles contained in the metal structure (texture) are refined by adding a specific amount of Zr. Mn and Cr did not exhibit a significant Si particle refinement effect, but Zr exhibited a significant Si particle refinement effect.
  • the fatigue strength was improved by thus suppressing fatigue propagation.
  • the extruded material have an average Si particle size of 20 ⁇ m or less, and an average crystal grain size of 30 ⁇ m or less.
  • the content range of each component of the aluminum alloy is adjusted for the following reasons.
  • Si forms an Mg 2 Si precipitate with Mg, and provides the aluminum alloy with strength through age hardening.
  • the Si particles contained in the metal structure also provide the aluminum alloy with wear resistance.
  • the Mg content is set to 0.1 mass % or more taking account of these effects.
  • the Mg content is preferably set to 0.3 mass % or more when it is desired to provide the aluminum alloy with higher strength.
  • the Mg content is set to 0.5 mass % or less, and preferably 0.45 mass % or less.
  • the Si content is set to 3.0 mass % or more.
  • the Si content is preferably set to 4.1 to 6.1 mass % when it is desired to provide the aluminum alloy with stable wear resistance.
  • the Si content is preferably set to 8.0 mass % or less.
  • Cu improves the strength of the aluminum alloy while ensuring caulking properties. Since Cu is solid-dissolved to a certain extent, the strength and the machinability of the aluminum alloy are improved due to solid-solution hardening.
  • the Cu content is set to 0.01 mass % or more taking account of these effects. If the Cu content is too high, potential difference corrosion tends to occur. Therefore, the Cu content is set to 0.50 mass % or less. The Cu content is preferably set to 0.10 to 0.20 mass %.
  • the upper limit of the Cu content is more preferably set to 0.14 mass % or less.
  • Fe particles are dispersed at the crystal grain boundaries, and chips break from the Fe particles. As a result, the machinability of the aluminum alloy is improved.
  • the Fe content is preferably set to 0.40 mass % or more taking account of these effects. If the Fe content exceeds 0.9 mass %, a large number of Fe particles may precipitate at the crystal grain boundaries. In this case, the caulking properties of the aluminum alloy may deteriorate due to a decrease in toughness.
  • the Fe content is set to 0.4 to 0.9 mass %, and preferably 0.5 to 0.8 mass %.
  • Zr suppresses recrystallization, and refines the crystal grains. Moreover, fatigue propagation is suppressed due to refinement of the Si particles, so that the fatigue strength and the machinability of the aluminum alloy are improved.
  • the Zr content is set to 0.1 mass % or more in order to obtain these effects. If the Zr content exceeds 0.5 mass %, Zr may produce a primary crystal product, so that the caulking properties of the aluminum alloy may deteriorate.
  • the Zr content is set to 0.1 to 0.5 mass %.
  • the Zr content is set to 0.14 mass % or more when it is desired to further refine the Si particles.
  • the Zr content is set to 0.3 mass % or less from the viewpoint of caulking properties.
  • Mn has a small Si particle refinement effect. However, Mn suppresses recrystallization, and refines the crystal grains.
  • Mn contributes to an improvement in fatigue strength and machinability through refinement of the crystal grains.
  • the Mn content is set to 0.01 mass % or more in order to obtain these effects. If Mn precipitates at the crystal grain boundaries, potential difference corrosion and a decrease in caulking properties may occur. Therefore, the Mn content is set to 0.5 mass % or less.
  • the Mn content is preferably set to 0.05 to 0.15 mass %.
  • Cr has a small Si particle refinement effect. However, Cr suppresses recrystallization, and refines the crystal grains.
  • the Cr content is set to 0.01 mass % or more in order to obtain these effects. Since Cr may produce a primary crystal product, and may cause a decrease in caulking properties, the Cr content is set to 0.5 mass % or less.
  • the Cr content is preferably set to 0.05 to 0.15 mass %.
  • Ti refines the crystal grains.
  • the machinability of the aluminum alloy is improved when the Ti content is small. If the Ti content exceeds 0.1 mass %, the life of a cutting tool may decrease.
  • the Ti content is set to 0.01 to 0.1 mass %.
  • the wear-resistant aluminum alloy extruded material according to one embodiment of the invention exhibits caulking properties and machinability while maintaining wear resistance as a result of adjusting the content of Si, Mg, Fe, Cu, Mn, and Cr. Moreover, the Si particles can be refined by adjusting the Zr content, so that the fatigue strength of the aluminum alloy extruded material can be improved.
  • An 8-inch billet was cast at a casting speed of 70 to 100 mm/min (see FIG. 1 ) using a molten metal containing the chemical components shown in FIG. 1 (balance: aluminum and unavoidable impurities), and homogenized at 460 to 590° C. for 6 hours or more.
  • Zn shown in FIG. 1 is regarded as impurities. No problem occurs if the Zn content is 0.05 mass % or less.
  • the billet was preheated to 450 to 510° C., and extruded into a rectangular extruded material having dimensions of about 40 ⁇ 100 mm at an extrusion speed of 5 to 10 m/min.
  • a T6 heat treatment was performed by quenching the extruded material at the end of the die through water-cooling immediately after extrusion, and subjecting the extruded material to artificial aging at 160 to 195° C. for 2 to 8 hours.
  • the resulting extruded material was evaluated under the following conditions. The results are shown in FIG. 2 .
  • a JIS No. 1(1-8) specimen (rotating bending fatigue test specimen) was prepared using the extruded material in accordance with JIS Z 2274. The specimen was subjected to a fatigue test using an Ono-type rotating bending fatigue tester conforming to the JIS standard. The fatigue strength of the specimen was calculated from the resulting S-N curve.
  • a JIS No. 13B tensile test specimen was prepared using the extruded material in accordance with JIS Z 2241. The specimen was subjected to a tensile test using a tensile tester conforming to the JIS standard to measure the tensile strength, the 0.2% proof stress, and the elongation at break of the specimen.
  • the surface hardness of the extruded material was measured using a Rockwell B scale hardness tester.
  • the caulking properties were measured using a cold upsetting test method.
  • a specimen (diameter: 14 mm, height: 21 mm) was sampled from the extruded material, and subjected to cold upsetting press in the axial direction to determine the critical upsetting ratio when microcracks started to occur in the side surface of the specimen.
  • the critical upsetting ratio was calculated by the following expression.
  • ⁇ hc [( h 0 ⁇ hc )/ h 0] ⁇ 100
  • ⁇ hc critical upsetting ratio (%)
  • h0 original height of specimen
  • hc height of specimen when cracks occurred
  • the test was performed at room temperature and a compression rate of 10 mm/s using a tester “Autograph” (25 t) (manufactured by Shimadzu Corporation).
  • the cutting length (20 mm or less) shown in FIG. 2 refers to the maximum chip length.
  • the maximum chip length refers to the maximum length of chips produced under the following test conditions.
  • Chip test conditions cutting tool: step drill (4.2 ⁇ 6.8 (diameter)), rotational speed: 1200 rpm, feed: 0.05 mm/rev, processing amount: 15 mm, number of holes formed: 3, cutting oil: used
  • the wear resistance was measured using a frictional wear tester (“EFM-III-F” manufactured by Orientec Co., Ltd.).
  • the pin (diameter: 5 mm, height: 8 mm) was formed of an SCr20 (carburized quenched) material.
  • the specimen disk (diameter: 60 mm, height: 5 mm) was cut from the extruded material, and processed to have a surface roughness of 1.6 Z or less and a flatness of 0.01 or less.
  • a brake fluid was used as a lubricant.
  • the rotational speed was 160 rpm
  • the testing time was 50 hours
  • the applied load was 20 MPa.
  • the wear rate of the wear-out part of the specimen disk was measured using a roughness measuring instrument.
  • a specimen 35 (L) ⁇ 35 (W) ⁇ 35 (H) (see FIG. 6 ) was cut from the extruded material.
  • a dacrotized bolt was assembled to the center threaded portion of the specimen. The basic cycle shown in FIG. 6 was repeated ten times.
  • the corrosion resistance was evaluated by measuring the corrosion depth of the contact surface with the dacrotized bolt and an area around the contact surface.
  • a sample was cut from the center area of the extruded material, mirror-finished, etched, and then observed using an optical microscope (magnification: 400).
  • the measured value in the lengthwise direction was used as the crystal grain size or the Si particle size.
  • a sample was cut from the surface area of the extruded material, mirror-finished, etched, and then observed using an optical microscope (magnification: 50) to measure the surface recrystallization depth in an average area.
  • Each property target value shown in FIG. 2 indicates a value that is expected to be required to reduce the size and the weight of an automotive ABS body.
  • the extruded materials obtained in the examples according to the invention had a high fatigue strength (i.e., 130 MPa or more) as compared with the extruded materials obtained in the comparative examples.
  • the target average Si particle size was not achieved in Comparative Example 6 in which Mn was added in an amount of 0.50 mass %, and Comparative Examples 5 and 6 in which Cr was added in an amount of 0.30 mass %.
  • Example 1 The extruded material obtained in Example 1 was compared with the extruded material obtained in Comparative Example 1.
  • FIG. 3 shows the measurement results for the S-N curve
  • FIG. 4 shows the measurement results for the average crystal grain size and the average Si particle size
  • FIG. 5 shows the measurement results for the surface recrystallization depth.
  • the extruded materials obtained in Comparative Example 7 had poor wear resistance due to low Si content and high Mg content.
  • the target fatigue strength was not achieved in Comparative Examples 3 and 4 although the composition was similar to those of the examples except that Zr was not added.
  • the aluminum alloy extruded material according to the invention exhibits excellent wear resistance, caulking properties, machinability, and fatigue strength
  • the aluminum alloy extruded material may be used for automotive brake parts, hydraulic control parts of industrial machines, and the like.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Powder Metallurgy (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
US13/287,353 2009-06-29 2011-11-02 Wear-resistant aluminum alloy extruded material exhibiting excellent fatigue strength and machinability Abandoned US20120045359A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2009-154439 2009-06-29
JP2009154439 2009-06-29
PCT/JP2010/060644 WO2011001870A1 (ja) 2009-06-29 2010-06-23 疲労強度及び切削性に優れた耐摩耗性アルミニウム合金押出材

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2010/060644 Continuation WO2011001870A1 (ja) 2009-06-29 2010-06-23 疲労強度及び切削性に優れた耐摩耗性アルミニウム合金押出材

Publications (1)

Publication Number Publication Date
US20120045359A1 true US20120045359A1 (en) 2012-02-23

Family

ID=43410945

Family Applications (1)

Application Number Title Priority Date Filing Date
US13/287,353 Abandoned US20120045359A1 (en) 2009-06-29 2011-11-02 Wear-resistant aluminum alloy extruded material exhibiting excellent fatigue strength and machinability

Country Status (5)

Country Link
US (1) US20120045359A1 (ja)
EP (1) EP2450462B1 (ja)
JP (1) JP4755725B2 (ja)
CN (1) CN102459672A (ja)
WO (1) WO2011001870A1 (ja)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103849797A (zh) * 2014-01-16 2014-06-11 滁州东润电子科技有限公司 一种led灯具散热器铸造铝合金材料及其制备工艺
KR102156008B1 (ko) * 2014-07-31 2020-09-15 가부시키가이샤 고베 세이코쇼 절삭성이 우수한 알루미늄 합금 압출재 및 그의 제조 방법
WO2018017894A1 (en) 2016-07-21 2018-01-25 Johnson & Johnson Visioncare, Inc. Biomedical device including encapsulation
CN107022703A (zh) * 2017-04-27 2017-08-08 马鞍山常裕机械设备有限公司 一种汽车轮毂用高强度铝合金材料及其生产工艺
JP6389546B1 (ja) * 2017-05-12 2018-09-12 株式会社Uacj 磁気ディスク用アルミニウム合金基板及びその製造方法、ならびに、この磁気ディスク用アルミニウム合金基板を用いた磁気ディスク
CN107245614B (zh) * 2017-07-27 2019-01-22 广州致远新材料科技有限公司 一种耐磨铝合金及其用途
CN109050870B (zh) * 2018-11-13 2019-02-22 烟台工程职业技术学院 一种快速拆装件及其加工方法
CN115700288A (zh) * 2022-10-26 2023-02-07 江苏艾速特低碳科技有限公司 一种汽车排气门铝基合金材料及其制备方法与应用

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020197506A1 (en) * 1999-04-28 2002-12-26 Seizo Ueno Aluminum alloy for a welded construction and welded joint using the same
JP2003147468A (ja) * 2001-11-09 2003-05-21 Kobe Steel Ltd 切削用Ａｌ−Ｍｇ−Ｓｉ系アルミニウム合金押出材
US20030143102A1 (en) * 2001-07-25 2003-07-31 Showa Denko K.K. Aluminum alloy excellent in cutting ability, aluminum alloy materials and manufacturing method thereof
US6607615B1 (en) * 1997-10-31 2003-08-19 The Furukawa Electric Co., Ltd. Extruded material of aluminum alloy for structural members of automobile body and method of manufacturing the same
JP2004277762A (ja) * 2003-03-13 2004-10-07 Nippon Light Metal Co Ltd 冷間加工用熱処理型アルミニウム合金素材の製造方法
US20050109429A1 (en) * 2003-11-21 2005-05-26 Showa Denko K.K. Aluminum alloy, bar-like material, forge-formed article, machine-formed article, wear-resistant aluminum alloy with excellent anodized coat using the same and production methods thereof

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06240399A (ja) * 1993-02-16 1994-08-30 Honda Motor Co Ltd 切欠き疲労強度の優れた耐熱アルミニウム合金
JP3107517B2 (ja) 1995-03-30 2000-11-13 株式会社神戸製鋼所 切削性に優れる高耐食アルミニウム合金押出材
JP3654695B2 (ja) * 1995-12-25 2005-06-02 アイシン軽金属株式会社 耐摩耗性アルミニウム合金
EP1413636B9 (en) * 2001-07-25 2009-10-21 Showa Denko K.K. Aluminum alloy excellent in machinability and aluminum alloy material and method for production thereof
ATE419404T1 (de) * 2002-02-28 2009-01-15 Aisin Keikinzoku Co Ltd Abriebfeste aluminiumlegierung mit hervorragendem stapelverhalten und daraus hergestelltes stranggepresstes produkt
JP4189974B2 (ja) * 2003-09-01 2008-12-03 アイシン軽金属株式会社 切削性・かしめ性・耐摩耗性に優れたアルミニウム合金押出材

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6607615B1 (en) * 1997-10-31 2003-08-19 The Furukawa Electric Co., Ltd. Extruded material of aluminum alloy for structural members of automobile body and method of manufacturing the same
US20020197506A1 (en) * 1999-04-28 2002-12-26 Seizo Ueno Aluminum alloy for a welded construction and welded joint using the same
US20030143102A1 (en) * 2001-07-25 2003-07-31 Showa Denko K.K. Aluminum alloy excellent in cutting ability, aluminum alloy materials and manufacturing method thereof
JP2003147468A (ja) * 2001-11-09 2003-05-21 Kobe Steel Ltd 切削用Ａｌ−Ｍｇ−Ｓｉ系アルミニウム合金押出材
JP2004277762A (ja) * 2003-03-13 2004-10-07 Nippon Light Metal Co Ltd 冷間加工用熱処理型アルミニウム合金素材の製造方法
US20050109429A1 (en) * 2003-11-21 2005-05-26 Showa Denko K.K. Aluminum alloy, bar-like material, forge-formed article, machine-formed article, wear-resistant aluminum alloy with excellent anodized coat using the same and production methods thereof

Also Published As

Publication number Publication date
EP2450462A4 (en) 2016-07-27
WO2011001870A1 (ja) 2011-01-06
CN102459672A (zh) 2012-05-16
JP4755725B2 (ja) 2011-08-24
JPWO2011001870A1 (ja) 2012-12-13
EP2450462A1 (en) 2012-05-09
EP2450462B1 (en) 2017-03-22

Similar Documents

Publication Publication Date Title
US20120045359A1 (en) Wear-resistant aluminum alloy extruded material exhibiting excellent fatigue strength and machinability
US7648594B2 (en) Extruded aluminum alloy which excels in machinability, caulking properties, and wear resistance
JP6534687B2 (ja) 高張力黄銅合金及び合金製品
JP7072526B2 (ja) 無鉛高張力黄銅合金及び高張力黄銅合金製品
US9803264B2 (en) High-plasticity free-cutting zinc alloy
EP2811043B1 (en) High-strength aluminum alloy extrudate with excellent corrosion resistance, ductility, and hardenability and process for producing same
WO2020261611A1 (ja) 快削性銅合金、及び、快削性銅合金の製造方法
JP2021042459A (ja) 快削性銅合金、及び、快削性銅合金の製造方法
JP6937663B2 (ja) かしめ性及び疲労強度に優れた耐摩耗性アルミニウム合金押出材及びそれに用いるアルミニウム合金
US7473327B2 (en) Wear-resistant aluminum alloy excellent in caulking property and extruded product made thereof
WO2020261666A1 (ja) 快削性銅合金、及び、快削性銅合金の製造方法
Latif Effect of loading rates and single edge notch bending (SENB) specimen thicknesses on shear lips formation for Al6061 alloy
CN102952974A (zh) 耐磨损性、敛缝性和疲劳强度优良的铝合金
KR20130000341A (ko) 자동차 부품 압출용 고강도 알루미늄 합금
JP2005256015A (ja) 切削性に優れた耐摩耗性アルミニウム合金押出材
Pai et al. A Finite Element Approach to Conduct Machinability Studies on Age-Hardened AA6061 Matrix Hybrid Composites.
CN1869267A (zh) 具有改善性能的用于冷成形操作的工具
Babu et al. Optimization of Process Parameters of Cyclic Expansion Extrusion Process for Effective Grain Refinement of Al-Mg-Si Alloy
JP2004238739A (ja) 耐摩耗性アルミニウム合金
Hassani et al. The effects of friction stir processing on the wear behavior of cast AZ91C magnesium alloy
JPWO2021117528A1 (ja) 快削性銅合金、及び、快削性銅合金の製造方法
WO2019007906A1 (en) CORROSIVE ZINC ALLOY CONTAINING TITANIUM

Legal Events

Date Code Title Description
AS Assignment

Owner name: AISIN KEIKINZOKU CO., LTD., JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SHIBATA, KARIN;REEL/FRAME:027162/0320

Effective date: 20110926

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION