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I am working with white cast irons to make ore grinding balls and I want to get a white cast iron alloy that has good anti-wear properties and high impact resistance, what chemical composition(s) would you recommend for making these alloys for ore grinding balls? like copper ores?

------------------------------
Giancarlo Sanchez Chavez
UNSA
Miraflores
947822222
------------------------------

Giancarlo,
I am still a fan of the 15-3-1 alloy. It can have adequate toughness for many ore handling and grinding applications and is less expensive than the higher chrome white irons. The next trick is choosing the right heat treatment. You have not said anything about the mill where you are going to use these balls. Is it a 2 meter mill or a 8 meter semi autogenous (SAG) mill? Are you using  small 4 cm or fairly large 13 cm balls? If you have high impact you want to convert the retained austenite to martensite. If the balls are mostly failing due to abrasive wear you might what to heat treat for higher hardness and loose some toughness. Despite the longer life of the white iron balls you might find high carbon steel balls are more economical. The ores, you say you are grinding copper ores, can chemically attack the matrix and cause accelerated wear of the white iron, particularly if there is enough carbon in the alloy to tie up all the chrome in which case you might be better off with a hypoeutectic 20 or 25 wt % chrome alloy.  So sorry to say, there is not an easy "use this"  answer. (in my opinion.)

------------------------------
Joseph Tylczak
Metallurgist
Department of Energy, National Energy Technology Laboratory
Albany OR
(541) 928-2193
------------------------------

Original Message:
Sent: 01-27-2023 10:32
From: Giancarlo Sanchez Chavez
Subject: White cast iron alloy question

I am working with white cast irons to make ore grinding balls and I want to get a white cast iron alloy that has good anti-wear properties and high impact resistance, what chemical composition(s) would you recommend for making these alloys for ore grinding balls? like copper ores?

------------------------------
Giancarlo Sanchez Chavez
UNSA
Miraflores
947822222
------------------------------

Original Message:
Sent: 1/28/2023 6:29:00 PM
From: Joseph Tylczak
Subject: RE: White cast iron alloy question

Giancarlo,
I am still a fan of the 15-3-1 alloy. It can have adequate toughness for many ore handling and grinding applications and is less expensive than the higher chrome white irons. The next trick is choosing the right heat treatment. You have not said anything about the mill where you are going to use these balls. Is it a 2 meter mill or a 8 meter semi autogenous (SAG) mill? Are you using  small 4 cm or fairly large 13 cm balls? If you have high impact you want to convert the retained austenite to martensite. If the balls are mostly failing due to abrasive wear you might what to heat treat for higher hardness and loose some toughness. Despite the longer life of the white iron balls you might find high carbon steel balls are more economical. The ores, you say you are grinding copper ores, can chemically attack the matrix and cause accelerated wear of the white iron, particularly if there is enough carbon in the alloy to tie up all the chrome in which case you might be better off with a hypoeutectic 20 or 25 wt % chrome alloy.  So sorry to say, there is not an easy "use this"  answer. (in my opinion.)

------------------------------
Joseph Tylczak
Metallurgist
Department of Energy, National Energy Technology Laboratory
Albany OR
(541) 928-2193
------------------------------

Original Message:
Sent: 01-27-2023 10:32
From: Giancarlo Sanchez Chavez
Subject: White cast iron alloy question

I am working with white cast irons to make ore grinding balls and I want to get a white cast iron alloy that has good anti-wear properties and high impact resistance, what chemical composition(s) would you recommend for making these alloys for ore grinding balls? like copper ores?

------------------------------
Giancarlo Sanchez Chavez
UNSA
Miraflores
947822222
------------------------------

Hi Harold
I am participating in a research project and our objective is to improve the properties of grinding balls for copper mining in my region. I do not have the bond index of the mineral that the mining companies with which they work and some suppliers manufacture grinds of various hardnesses and do not mention the bond index for the hardness of the ball. So I think my question is a bit general in relation to what you illustrate. I will take you at your word and I would like to continue asking you about the doubts that arise in my university project.
Hugs

------------------------------
Giancarlo Sanchez Chavez
UNSA
Miraflores
947822222
------------------------------

Original Message:
Sent: 01-29-2023 12:55
From: Harold Mulenga
Subject: White cast iron alloy question

Giancarlo,

For more beneficial advice on the grinding media chemical composition to settle, kindly share the Bond work index for the ore you are treating, the diameter and length of the Mill being used for milling the ore and the type of grinding applicable (Attrition/abrasion or impact grinding). These details will help in recommending the right grinding media to use.

Hammer Forged grinding media is preferred for impact while High Chrome white iron is good for abrasion/attrition grinding. 

Feel free to get in touch. I'm servicing the copper mining industry here in Zambia on both SAG and Ball Mills and supplying both High Chrome and Hammer Forged grinding media for years now and I'm working with SCAW Limited the Largest Foundry company in Zambia.

.......................................

Harold K. Mulenga

Original Message:
Sent: 1/28/2023 6:29:00 PM
From: Joseph Tylczak
Subject: RE: White cast iron alloy question

Giancarlo,
I am still a fan of the 15-3-1 alloy. It can have adequate toughness for many ore handling and grinding applications and is less expensive than the higher chrome white irons. The next trick is choosing the right heat treatment. You have not said anything about the mill where you are going to use these balls. Is it a 2 meter mill or a 8 meter semi autogenous (SAG) mill? Are you using  small 4 cm or fairly large 13 cm balls? If you have high impact you want to convert the retained austenite to martensite. If the balls are mostly failing due to abrasive wear you might what to heat treat for higher hardness and loose some toughness. Despite the longer life of the white iron balls you might find high carbon steel balls are more economical. The ores, you say you are grinding copper ores, can chemically attack the matrix and cause accelerated wear of the white iron, particularly if there is enough carbon in the alloy to tie up all the chrome in which case you might be better off with a hypoeutectic 20 or 25 wt % chrome alloy.  So sorry to say, there is not an easy "use this"  answer. (in my opinion.)

------------------------------
Joseph Tylczak
Metallurgist
Department of Energy, National Energy Technology Laboratory
Albany OR
(541) 928-2193

Original Message:
Sent: 01-27-2023 10:32
From: Giancarlo Sanchez Chavez
Subject: White cast iron alloy question

I am working with white cast irons to make ore grinding balls and I want to get a white cast iron alloy that has good anti-wear properties and high impact resistance, what chemical composition(s) would you recommend for making these alloys for ore grinding balls? like copper ores?

------------------------------
Giancarlo Sanchez Chavez
UNSA
Miraflores
947822222
------------------------------

hi joseph
In my country, Peru, there is a large mining industry that can use 8-meter semi-autogenous mills (SAG) and they want to provide an alloy that is resistant for them. And some companies indicate that the balls they offer do not have the life time that the suppliers offer them and fail early. And I understand that answering my doubts has many questions behind.
Thank you for your response and if we could continue talking about this matter it would be ideal.
Hugs

------------------------------
Giancarlo Sanchez Chavez
UNSA
Miraflores
947822222
------------------------------

Original Message:
Sent: 01-28-2023 18:29
From: Joseph Tylczak
Subject: White cast iron alloy question

Giancarlo,
I am still a fan of the 15-3-1 alloy. It can have adequate toughness for many ore handling and grinding applications and is less expensive than the higher chrome white irons. The next trick is choosing the right heat treatment. You have not said anything about the mill where you are going to use these balls. Is it a 2 meter mill or a 8 meter semi autogenous (SAG) mill? Are you using  small 4 cm or fairly large 13 cm balls? If you have high impact you want to convert the retained austenite to martensite. If the balls are mostly failing due to abrasive wear you might what to heat treat for higher hardness and loose some toughness. Despite the longer life of the white iron balls you might find high carbon steel balls are more economical. The ores, you say you are grinding copper ores, can chemically attack the matrix and cause accelerated wear of the white iron, particularly if there is enough carbon in the alloy to tie up all the chrome in which case you might be better off with a hypoeutectic 20 or 25 wt % chrome alloy.  So sorry to say, there is not an easy "use this"  answer. (in my opinion.)

------------------------------
Joseph Tylczak
Metallurgist
Department of Energy, National Energy Technology Laboratory
Albany OR
(541) 928-2193

Original Message:
Sent: 01-27-2023 10:32
From: Giancarlo Sanchez Chavez
Subject: White cast iron alloy question

I am working with white cast irons to make ore grinding balls and I want to get a white cast iron alloy that has good anti-wear properties and high impact resistance, what chemical composition(s) would you recommend for making these alloys for ore grinding balls? like copper ores?

------------------------------
Giancarlo Sanchez Chavez
UNSA
Miraflores
947822222
------------------------------

Professor Chavez,
Sure, I would be happy to extend this conversation on improved grinding balls for copper ore further. One other caution on white iron balls  occurred to me. When concrete clinker grinding moved from steel balls, with I believe NiHard white iron lifters, to white iron balls, they suffered a lot of breakage of the lifters due to the different mechanical properties of the white iron balls. I believe the answer was to move to a tougher Cr Mo white iron lifter. I am working off of memory and I would need to check the details.

I would start by getting some of the balls in use and characterize their composition, hardness (center to edge) and how they were made (cast or forged).

------------------------------
Joseph Tylczak
Metallurgist
Albany OR

------------------------------

Original Message:
Sent: 02-11-2023 10:19
From: Giancarlo Sanchez Chavez
Subject: White cast iron alloy question

hi joseph
In my country, Peru, there is a large mining industry that can use 8-meter semi-autogenous mills (SAG) and they want to provide an alloy that is resistant for them. And some companies indicate that the balls they offer do not have the life time that the suppliers offer them and fail early. And I understand that answering my doubts has many questions behind.
Thank you for your response and if we could continue talking about this matter it would be ideal.
Hugs

------------------------------
Giancarlo Sanchez Chavez
UNSA
Miraflores
947822222

Original Message:
Sent: 01-28-2023 18:29
From: Joseph Tylczak
Subject: White cast iron alloy question

Giancarlo,
I am still a fan of the 15-3-1 alloy. It can have adequate toughness for many ore handling and grinding applications and is less expensive than the higher chrome white irons. The next trick is choosing the right heat treatment. You have not said anything about the mill where you are going to use these balls. Is it a 2 meter mill or a 8 meter semi autogenous (SAG) mill? Are you using  small 4 cm or fairly large 13 cm balls? If you have high impact you want to convert the retained austenite to martensite. If the balls are mostly failing due to abrasive wear you might what to heat treat for higher hardness and loose some toughness. Despite the longer life of the white iron balls you might find high carbon steel balls are more economical. The ores, you say you are grinding copper ores, can chemically attack the matrix and cause accelerated wear of the white iron, particularly if there is enough carbon in the alloy to tie up all the chrome in which case you might be better off with a hypoeutectic 20 or 25 wt % chrome alloy.  So sorry to say, there is not an easy "use this"  answer. (in my opinion.)

------------------------------
Joseph Tylczak
Metallurgist
Department of Energy, National Energy Technology Laboratory
Albany OR
(541) 928-2193

Original Message:
Sent: 01-27-2023 10:32
From: Giancarlo Sanchez Chavez
Subject: White cast iron alloy question

I am working with white cast irons to make ore grinding balls and I want to get a white cast iron alloy that has good anti-wear properties and high impact resistance, what chemical composition(s) would you recommend for making these alloys for ore grinding balls? like copper ores?

------------------------------
Giancarlo Sanchez Chavez
UNSA
Miraflores
947822222
------------------------------