CN105420469A - Machining method for high-shearing-force automobile engine connecting rod - Google Patents

Machining method for high-shearing-force automobile engine connecting rod Download PDF

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Publication number
CN105420469A
CN105420469A CN201510735003.4A CN201510735003A CN105420469A CN 105420469 A CN105420469 A CN 105420469A CN 201510735003 A CN201510735003 A CN 201510735003A CN 105420469 A CN105420469 A CN 105420469A
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China
Prior art keywords
connecting rod
treatment
parts
carry out
intake
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.)
Pending
Application number
CN201510735003.4A
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Chinese (zh)
Inventor
沈四海
沈军
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Hefei Haiyuan Machinery Co Ltd
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Hefei Haiyuan Machinery Co Ltd
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Priority to CN201510735003.4A priority Critical patent/CN105420469A/en
Publication of CN105420469A publication Critical patent/CN105420469A/en
Pending legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
    • B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
    • C21D1/76—Adjusting the composition of the atmosphere
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/04—Hardening by cooling below 0 degrees Celsius
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/008—Ferrous alloys, e.g. steel alloys containing tin
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/10—Ferrous alloys, e.g. steel alloys containing cobalt
    • C22C38/105—Ferrous alloys, e.g. steel alloys containing cobalt containing Co and Ni
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/60—Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
    • C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
    • C23C22/07—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing phosphates

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Shafts, Cranks, Connecting Bars, And Related Bearings (AREA)

Abstract

The invention discloses a machining method for a high-shearing-force automobile engine connecting rod. The preparation method comprises the steps that a rod blank is obtained through the casting technique; and chemical components of the rod blank are made to meet the requirement that the rod blank is composed of, by weight, 2.25-2.55% of C, 0.45-0.55% of Mo, 1.15-1.45% of Si, 0.12-0.16% of W, 0.015-0.035% of P, 0.005-0.015% of S, 0.15-0.25% of Ni, 0.025-0.045% of Mn, 0.02-0.03% of Sn, 0.02-0.05% of Co, 0.01-0.03% of Sb and the balance Fe. By means of the machining method, the problems of delayed fracture and fatigue fracture of the connecting rod under high strength are solved, connection is reliable when the connecting rod is in use, fracture is unlikely to occur, the service life of the connecting rod is prolonged, and using requirements of various industries in the society for the high-strength connecting rod are met.

Description

The strong connection rod of automobile engine working method of shearing force
Technical field
The present invention relates to the working method of bolt, the strong connection rod of automobile engine working method of especially a kind of shearing force.
Background technology
Most of connecting rod manufacture uses medium carbon steel and low alloy steel, and domestic traditional technology connecting rod blank material generally adopts 42CrMo, the quenched and tempered steel such as 35CrMo, 40MnVB, 45CrMnB and S43CVS1, the non-hardened and tempered steels such as 35MnV, 40MnS.In complete processing, the domestic and international connecting rod mode of production roughly has: forging, casting, powder metallurgy etc., and this year, connecting rod manufacture all adopted contour forging technique.
Given this, be necessary to provide a kind of more advanced processing method of engine connecting rod.
Summary of the invention
The object of the invention is to avoid weak point of the prior art, and provide a kind of shearing force strong connection rod of automobile engine working method.
Object of the present invention is as follows by the following technical programs:
The strong connection rod of automobile engine working method of shearing force, procedure of processing comprises:
A, obtain bar material blank by casting technique, the weight percent of each chemical composition of control lever material blank should meet following requirement: C2.25 ~ 2.55, Mo0.45 ~ 0.55, Si1.15 ~ 1.45, W0.12-0.16,0.015≤P≤0.035,0.005≤S≤0.015, Ni0.15 ~ 0.25, Mn0.025 ~ 0.045, Sn0.02 ~ 0.03,0.02≤Co≤0.05,0.01≤Sb≤0.03, surplus is iron;
B, carry out forging and molding processing to the bar material after casting, forge temperature and control as 700-750 DEG C, the impression inwall forging mould covers thin layer refractory paint, and the thickness of thin layer refractory paint is 40-60um, forges number of times 10-15 time;
C, carry out sub-zero treatment to the bar material after thermal treatment, liquid nitrogen temperature is-85 ~-110 DEG C, and the time of sub-zero treatment is 1-2 hour, and the isothermal time in liquid nitrogen is: the cross-sectional area of connecting rod be multiplied by 3 ~ 4min/mm 2, the boiling water that the bar material after sub-zero treatment, temperature having been gone back up to room temperature puts into 100 DEG C heats 60-80 minute;
D, bonderizing, first carry out skimming treatment with the washing of 15-18% sodium hydroxide solution, temperature controls between 55-65 DEG C, and the time is 18-20 minute, then washes; Carry out cleanup acid treatment with the washing of 40-45% carbonic acid soln again, temperature controls at 22-26 DEG C, and the time is 12-15 minute, then washes;
E, as cast condition connecting rod carry out surperficial Atmosphere controlling heat-treatment: pass into mixed gas in heat treated stove, nitrogen intake is at 120 ~ 130ml/min, methyl alcohol intake is at 40 ~ 50ml/min, methane intake is at 15 ~ 20ml/min, and its furnace gas atmosphere compositing range controls at a nitrogen content 45 ~ 50 parts, hydrogen content 28 ~ 30 parts, carbon dioxide content 10 ~ 12 parts.
Described as cast condition connecting rod carries out surperficial Atmosphere controlling heat-treatment: pass into mixed gas in heat treated stove, nitrogen intake is at 125ml/min, methyl alcohol intake is at 45ml/min, methane intake is at 18ml/min, and its furnace gas atmosphere compositing range controls at a nitrogen content 48 parts, hydrogen content 29 parts, carbon dioxide content 11 parts.
The invention solves delayed fracture and the repeated stress failure of high strength lower link, in use connect reliable, not frangibility, improves the connecting rod life-span, meets the upper every profession and trade of society to the user demand of high-strength connecting rod.The connection rod of automobile engine any surface finish that the present invention makes by said ratio, does not have the defects such as obvious crackle, peeling, wrinkle, and after electroplating nickel on surface, color and luster is consistent, good looking appearance.
Embodiment
The invention will be further described with the following Examples:
The strong connection rod of automobile engine working method of shearing force, procedure of processing comprises:
A, obtain bar material blank by casting technique, the weight percent of each chemical composition of control lever material blank should meet following requirement: C2.25 ~ 2.55, Mo0.45 ~ 0.55, Si1.15 ~ 1.45, W0.12-0.16,0.015≤P≤0.035,0.005≤S≤0.015, Ni0.15 ~ 0.25, Mn0.025 ~ 0.045, Sn0.02 ~ 0.03,0.02≤Co≤0.05,0.01≤Sb≤0.03, surplus is iron;
B, carry out forging and molding processing to the bar material after casting, forge temperature and control as 700-750 DEG C, the impression inwall forging mould covers thin layer refractory paint, and the thickness of thin layer refractory paint is 40-60um, forges number of times 10-15 time;
C, carry out sub-zero treatment to the bar material after thermal treatment, liquid nitrogen temperature is-85 ~-110 DEG C, and the time of sub-zero treatment is 1-2 hour, and the isothermal time in liquid nitrogen is: the cross-sectional area of connecting rod be multiplied by 3 ~ 4min/mm 2, the boiling water that the bar material after sub-zero treatment, temperature having been gone back up to room temperature puts into 100 DEG C heats 60-80 minute;
D, bonderizing, first carry out skimming treatment with the washing of 15-18% sodium hydroxide solution, temperature controls between 55-65 DEG C, and the time is 18-20 minute, then washes; Carry out cleanup acid treatment with the washing of 40-45% carbonic acid soln again, temperature controls at 22-26 DEG C, and the time is 12-15 minute, then washes;
E, as cast condition connecting rod carry out surperficial Atmosphere controlling heat-treatment: pass into mixed gas in heat treated stove, nitrogen intake is at 125ml/min, methyl alcohol intake is at 45ml/min, methane intake is at 18ml/min, and its furnace gas atmosphere compositing range controls at a nitrogen content 48 parts, hydrogen content 29 parts, carbon dioxide content 11 parts.
The bolt that the strong connection rod of automobile engine preparation method of shearing force of the present invention produces, as follows through its mechanical property numerical value of detection experiment, connecting rod centre hardness reaches 43-45HRC, rod surface hardness reaches 35-40HRC, shear strength reaches 940-980Mpa, yield strength reaches 850-900Mpa, unit elongation is greater than 12.5%, and relative reduction in area is greater than 30-32%, impelling strength 50-53J/cm 2.
Finally should be noted that; above embodiment is only for illustration of technical scheme of the present invention but not limiting the scope of the invention; although be explained in detail the present invention with reference to preferred embodiment; those of ordinary skill in the art is to be understood that; can modify to technical scheme of the present invention or equivalent replacement, and not depart from essence and the scope of technical solution of the present invention.

Claims (2)

1. the strong connection rod of automobile engine working method of shearing force, it is characterized in that, procedure of processing comprises:
A, obtain bar material blank by casting technique, the weight percent of each chemical composition of control lever material blank should meet following requirement: C2.25 ~ 2.55, Mo0.45 ~ 0.55, Si1.15 ~ 1.45, W0.12-0.16,0.015≤P≤0.035,0.005≤S≤0.015, Ni0.15 ~ 0.25, Mn0.025 ~ 0.045, Sn0.02 ~ 0.03,0.02≤Co≤0.05,0.01≤Sb≤0.03, surplus is iron;
B, carry out forging and molding processing to the bar material after casting, forge temperature and control as 700-750 DEG C, the impression inwall forging mould covers thin layer refractory paint, and the thickness of thin layer refractory paint is 40-60um, forges number of times 10-15 time;
C, carry out sub-zero treatment to the bar material after thermal treatment, liquid nitrogen temperature is-85 ~-110 DEG C, and the time of sub-zero treatment is 1-2 hour, and the isothermal time in liquid nitrogen is: the cross-sectional area of connecting rod be multiplied by 3 ~ 4min/mm 2, the boiling water that the bar material after sub-zero treatment, temperature having been gone back up to room temperature puts into 100 DEG C heats 60-80 minute;
D, bonderizing, first carry out skimming treatment with the washing of 15-18% sodium hydroxide solution, temperature controls between 55-65 DEG C, and the time is 18-20 minute, then washes; Carry out cleanup acid treatment with the washing of 40-45% carbonic acid soln again, temperature controls at 22-26 DEG C, and the time is 12-15 minute, then washes;
E, as cast condition connecting rod carry out surperficial Atmosphere controlling heat-treatment: pass into mixed gas in heat treated stove, nitrogen intake is at 120 ~ 130ml/min, methyl alcohol intake is at 40 ~ 50ml/min, methane intake is at 15 ~ 20ml/min, and its furnace gas atmosphere compositing range controls at a nitrogen content 45 ~ 50 parts, hydrogen content 28 ~ 30 parts, carbon dioxide content 10 ~ 12 parts.
2. the strong connection rod of automobile engine working method of shearing force according to claim 1, it is characterized in that: described as cast condition connecting rod carries out surperficial Atmosphere controlling heat-treatment: pass into mixed gas in heat treated stove, nitrogen intake is at 125ml/min, methyl alcohol intake is at 45ml/min, methane intake is at 18ml/min, and its furnace gas atmosphere compositing range controls at a nitrogen content 48 parts, hydrogen content 29 parts, carbon dioxide content 11 parts.
CN201510735003.4A 2015-11-03 2015-11-03 Machining method for high-shearing-force automobile engine connecting rod Pending CN105420469A (en)

Priority Applications (1)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106282828A (en) * 2016-08-31 2017-01-04 宁波瑞国精机工业有限公司 Hollow pillar
CN110139947A (en) * 2017-01-05 2019-08-16 杰富意钢铁株式会社 High strength cold rolled steel plate

Citations (7)

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Publication number Priority date Publication date Assignee Title
JP2003147478A (en) * 2001-11-12 2003-05-21 Sumitomo Metals (Kokura) Ltd Non-heattreated steel
CN1955498A (en) * 2005-10-26 2007-05-02 日产自动车株式会社 Non-heat treated steel for connecting rod and connecting rod formed of same
CN102989944A (en) * 2012-08-22 2013-03-27 昌利锻造有限公司 Forging method of expansion breaking connecting rod
CN103084525A (en) * 2012-12-04 2013-05-08 安徽六方重联机械股份有限公司 Method for machining connection rod bolt of diesel engine
CN103894613A (en) * 2012-12-28 2014-07-02 大连瓦特重机床有限公司 Powder forging process of connecting rods
CN104032205A (en) * 2014-06-11 2014-09-10 温州中普知识产权有限公司 Nodular cast iron alloy
CN104775081A (en) * 2015-04-21 2015-07-15 宝山钢铁股份有限公司 High-carbon non-tempered steel for breaking connecting rod and manufacturing method thereof

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003147478A (en) * 2001-11-12 2003-05-21 Sumitomo Metals (Kokura) Ltd Non-heattreated steel
CN1955498A (en) * 2005-10-26 2007-05-02 日产自动车株式会社 Non-heat treated steel for connecting rod and connecting rod formed of same
CN102989944A (en) * 2012-08-22 2013-03-27 昌利锻造有限公司 Forging method of expansion breaking connecting rod
CN103084525A (en) * 2012-12-04 2013-05-08 安徽六方重联机械股份有限公司 Method for machining connection rod bolt of diesel engine
CN103894613A (en) * 2012-12-28 2014-07-02 大连瓦特重机床有限公司 Powder forging process of connecting rods
CN104032205A (en) * 2014-06-11 2014-09-10 温州中普知识产权有限公司 Nodular cast iron alloy
CN104775081A (en) * 2015-04-21 2015-07-15 宝山钢铁股份有限公司 High-carbon non-tempered steel for breaking connecting rod and manufacturing method thereof

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106282828A (en) * 2016-08-31 2017-01-04 宁波瑞国精机工业有限公司 Hollow pillar
CN106282828B (en) * 2016-08-31 2017-12-01 宁波瑞国精机工业有限公司 Hollow pillar
CN110139947A (en) * 2017-01-05 2019-08-16 杰富意钢铁株式会社 High strength cold rolled steel plate
US11293103B2 (en) 2017-01-05 2022-04-05 Jfe Steel Corporation High-strength cold-rolled steel sheet

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