CN105112764A - High-strength high-hardness high-chromium cast iron plate hammer and preparation method thereof - Google Patents

Abstract

The invention discloses a high-strength high-hardness high-chromium cast iron plate hammer and a preparation method thereof. The high-strength high-hardness high-chromium cast iron plate hammer comprises the following chemical components by mass percent: 23.4-29.8% of Cr, 4.2-5.6% of Ni, 1.2-1.8% of Mo, 1.8-2.6% of Si, 3.2-4.0% of C, 0.25-0.45% of Mn, 1.4-2.2% of Zr, 1.0-1.5% of Ti, 0.3-0.7% of Ta, 0.5-1.0% of Mg, 0.4-0.6% of Cu, 0.3-0.5% of Al, 0.05-0.1% of Nd, 0.03-0.06% of Er, 0.03% or less of S, 0.06% or less of P and the balance Fe. The cast iron plate hammer prepared through the preparation method is good in comprehensive property, high in mechanical strength, hardness and abrasion resistance, low in cost, durable in use, and wide in market prospect, and is safe and reliable; and the production technology is simple and is high in efficiency.

Description

A kind of high strength and high hardness rich chromium cast iron bar and preparation method thereof

Technical field

The present invention relates to cast iron materials technical field, be specifically related to a kind of high strength and high hardness rich chromium cast iron bar and preparation method thereof.

Background technology

Crusher is the widely used a kind of crushing mechanism equipment of industry such as building, metallurgy, mine, cement.Wherein bar is the main abrasion piece of crusher, material smashes by it in high speed rotating, and workpiece surface bears the reactive force of material simultaneously with it, and Working environment is very severe, particularly when the difficulty of broken high strength, high rigidity breaks material, require higher to the obdurability of material.Although common rich chromium cast iron has good wear resistance, its intensity and hardness are not high, and in use procedure, bar easily occurs phenomenon of rupture, thus shutdown can be caused to stop production, and also may cause the damage of crusher time serious.

Summary of the invention

The object of the invention is to for the deficiencies in the prior art, a kind of high strength and high hardness rich chromium cast iron bar and preparation method thereof is provided.

For achieving the above object, the technical solution used in the present invention is as follows:

A kind of high strength and high hardness rich chromium cast iron bar, its each chemical composition and mass percent are: Cr23.4-29.8, Ni4.2-5.6, Mo1.2-1.8, Si1.8-2.6, C3.2-4.0, Mn0.25-0.45, Zr1.4-2.2, Ti1.0-1.5, Ta0.3-0.7, Mg0.5-1.0, Cu0.4-0.6, Al0.3-0.5, Nd0.05-0.1, Er0.03-0.06, S≤0.03, P≤0.06, and surplus is Fe.

A preparation method for high strength and high hardness rich chromium cast iron bar, comprises the following steps:

(1) in medium-frequency induction furnace, melting is carried out, first add steel scrap, scrap iron, the pig iron and ferrochrome melting down, add ferronickel, molybdenum-iron, ferromanganese, ferrotianium, copper, tantalum successively again, hot metal composition is adjusted after its all fusing, before coming out of the stove, successively add ferrosilicon and ferrozirconium in 8-12min, before coming out of the stove, in 3-5min, add fine aluminium carry out deoxidation, before coming out of the stove, carry out chemical composition analysis, can come out of the stove after qualified, molten iron tapping temperature controls at 1530-1570 DEG C;

(2) in bag, pour rare earth magnesium ferrosilicon alloy alterant and carry out rotten inoculation, alterant carries out the preheating of 200-300 DEG C before using, rotten inoculation temperature is 1495-1525 DEG C, then in bag, be sprinkled into appropriate perlite insulation gather the covering of slag insulating covering agent, and calm 5-8min, pour into a mould after skimming, teeming temperature controls at 1440-1470 DEG C;

(3) cast iron obtained above is heat-treated: be first heated to 930-970 DEG C, insulation 2-4h, tempering 5-8h at 360-420 DEG C again after cold quenching, then 680-740 DEG C is heated to, insulation 1-2h, reheats to 1040-1120 DEG C, insulation 4-5h, tempering 4-6h at 240-280 DEG C again after dry quenching, air cooling is to room temperature.

Beneficial effect of the present invention:

(1) present component is reasonable in design, adds the multiple elements such as appropriate Ni, Mo, Zr, Ta at control Cr content on the basis of 23.4-29.8%, mainly plays the effect of strengthening matrix, thinning microstructure, thus puies forward heavy alloyed hardness and intensity.

(2) reasonable heat treatment process of the present invention, the stability of primary austenite in rich chromium cast iron can be made to decline, in process of cooling subsequently, change martensitic stucture into, the pattern of carbide also significantly improves simultaneously, in mechanical property, then show as higher hardness and intensity.

(3) the cast iron bar over-all properties that obtains of the present invention is good, and existing high physical strength, has again high hardness and wear resistance, and production technique is simple, and efficiency is high, and cost is low, durable in use, safe and reliable, has wide market outlook.

Embodiment

A kind of high strength and high hardness rich chromium cast iron bar, its each chemical composition and mass percent are: Cr23.4-29.8, Ni4.2-5.6, Mo1.2-1.8, Si1.8-2.6, C3.2-4.0, Mn0.25-0.45, Zr1.4-2.2, Ti1.0-1.5, Ta0.3-0.7, Mg0.5-1.0, Cu0.4-0.6, Al0.3-0.5, Nd0.05-0.1, Er0.03-0.06, S≤0.03, P≤0.06, and surplus is Fe.

A preparation method for high strength and high hardness rich chromium cast iron bar, comprises the following steps:

(1) in medium-frequency induction furnace, melting is carried out, first add steel scrap, scrap iron, the pig iron and ferrochrome melting down, add ferronickel, molybdenum-iron, ferromanganese, ferrotianium, copper, tantalum successively again, hot metal composition is adjusted after its all fusing, before coming out of the stove, successively add ferrosilicon and ferrozirconium in 8-12min, before coming out of the stove, in 3-5min, add fine aluminium carry out deoxidation, before coming out of the stove, carry out chemical composition analysis, can come out of the stove after qualified, molten iron tapping temperature controls at 1530-1570 DEG C;

(2) in bag, pour rare earth magnesium ferrosilicon alloy alterant and carry out rotten inoculation, alterant carries out the preheating of 200-300 DEG C before using, rotten inoculation temperature is 1495-1525 DEG C, then in bag, be sprinkled into appropriate perlite insulation gather the covering of slag insulating covering agent, and calm 5-8min, pour into a mould after skimming, teeming temperature controls at 1440-1470 DEG C;

(3) cast iron obtained above is heat-treated: be first heated to 930-970 DEG C, insulation 2-4h, tempering 5-8h at 360-420 DEG C again after cold quenching, then 680-740 DEG C is heated to, insulation 1-2h, reheats to 1040-1120 DEG C, insulation 4-5h, tempering 4-6h at 240-280 DEG C again after dry quenching, air cooling is to room temperature.

Through inspection, commercialization studies and is divided into: Cr25.62%, Ni4.98%, Mo1.51%, Si2.07%, C3.63%, Mn0.38%, Zr1.72%, Ti1.11%, Ta0.52%, Mg0.75%, Cu0.56%, Al0.44%, Nd0.062%, Er0.047%, S0.022%, P0.048%, and surplus is Fe.Mechanical property is: bending strength: 906MPa, hardness: 76.3HRC, impelling strength: 19.8J/cm ².

Claims (2)

1. a high strength and high hardness rich chromium cast iron bar, it is characterized in that, its each chemical composition and mass percent are: Cr23.4-29.8, Ni4.2-5.6, Mo1.2-1.8, Si1.8-2.6, C3.2-4.0, Mn0.25-0.45, Zr1.4-2.2, Ti1.0-1.5, Ta0.3-0.7, Mg0.5-1.0, Cu0.4-0.6, Al0.3-0.5, Nd0.05-0.1, Er0.03-0.06, S≤0.03, P≤0.06, and surplus is Fe.

2. a preparation method for high strength and high hardness rich chromium cast iron bar as claimed in claim 1, is characterized in that comprising the following steps:

(1) in medium-frequency induction furnace, melting is carried out, first add steel scrap, scrap iron, the pig iron and ferrochrome melting down, add ferronickel, molybdenum-iron, ferromanganese, ferrotianium, copper, tantalum successively again, hot metal composition is adjusted after its all fusing, before coming out of the stove, successively add ferrosilicon and ferrozirconium in 8-12min, before coming out of the stove, in 3-5min, add fine aluminium carry out deoxidation, before coming out of the stove, carry out chemical composition analysis, can come out of the stove after qualified, molten iron tapping temperature controls at 1530-1570 DEG C;

(2) in bag, pour rare earth magnesium ferrosilicon alloy alterant and carry out rotten inoculation, alterant carries out the preheating of 200-300 DEG C before using, rotten inoculation temperature is 1495-1525 DEG C, then in bag, be sprinkled into appropriate perlite insulation gather the covering of slag insulating covering agent, and calm 5-8min, pour into a mould after skimming, teeming temperature controls at 1440-1470 DEG C;

(3) cast iron obtained above is heat-treated: be first heated to 930-970 DEG C, insulation 2-4h, tempering 5-8h at 360-420 DEG C again after cold quenching, then 680-740 DEG C is heated to, insulation 1-2h, reheats to 1040-1120 DEG C, insulation 4-5h, tempering 4-6h at 240-280 DEG C again after dry quenching, air cooling is to room temperature.