Vermicular cast iron alloy and internal combustion engine head

INTERNAL COMBUSTION ENGINE HEAD, containing the usual contents of the elements carbon (3.0 to 3.9%), manganese (0.1 to 0.6%), silicon (1.5 to 3.0%), magnesium (0.005 to 0.030%), cerium (0.005 to 0.030%), and residual elements such as sulfur (less than 0.030%) and phosphorus (less than 0.050%) are also present, characterized by the fact that it comprises the following alloy elements:

• Tin, existing in a range of 0.01% to 0.13% of the total amount of the alloy,
• Copper, existing in a range of 0.2% to 1.3% of the total amount of the alloy, and
• Molybdenum, existing in a range of 0.05% to 0.40% of the total amount of the alloy;
• these levels are balanced so that the Hot Resistance Factor (HRF) is between 0.5 and 1.7%, such factor defined by:
• HRF=3×(% Mo)+1×(% Sn)+0,25×(% Cu)(percentages by weight)
• wherein chromium is absent in the alloy, the matrix of the microstructure of said vermicular cast iron alloy comprises a fine pearlitic matrix comprising pearlite and with graphite particles predominantly in vermicular form and with the presence of graphite nodules up to 20%, and wherein an average interlamellar spacing of the pearlite is about 0.25 μm.

VERMICULAR CAST IRON ALLOY, comprising at least the following alloy elements, in the respective proportions:

• Carbon, existing in a range of 3.0% to 3.9% of the total amount of the alloy,
• Manganese, existing in a range of 0.1% to 0.6% of the total amount of the alloy,
• Silicon, existing in a range of 1.5% to 3.0% of the total amount of the alloy,
• Magnesium, existing in a range of 0.00% to 0.030% of the total amount of the alloy,
• Cerium, existing in a range of 0.005% to 0.030% of the total amount of the alloy,
• Sulfur, existing in a range of less than 0,030% of the total amount of the alloy
• Phosphorus, existing in a range of less than 0.050% of the total amount of the alloy,
• said vermicular cast iron alloy being especially characterized by the fact that it further comprises the following alloy elements, in the respective proportions:
• Tin, existing in a range of 0.01% to 0.13% of the total amount of the alloy,
• Copper, existing in a range of 0.2% to 1.3% of the total amount of the alloy, and
• Molybdenum, existing in a range of 0.05% to 0.40% of the total amount of the alloy;
• these levels are balanced so that the Hot Resistance Factor (HRF) is between 0.5 and 1.7%, such factor defined by:
• HRF=3×(% Mo)+1×(% Sn)+0,25×(% Cu)(percentages by weight)
• wherein chromium is absent in the alloy, the matrix of the microstructure of said vermicular cast iron alloy comprises a fine pearlitic matrix comprising pearlite and with graphite particles predominantly in vermicular form and with the presence of graphite nodules up to 20%, and wherein an average interlamellar spacing of the pearlite is about 0.25 μm.

INTERNAL COMBUSTION ENGINE HEAD, being characterized by the fact that it is made of a vermicular cast iron alloy comprising the following alloy elements, in the respective proportions:

• Carbon, existing in a range of 3.0% to 3.9% of the total amount of the alloy,
• Manganese, existing in a range of 0.1% to 0.6% of the total amount of the alloy,
• Silicon, existing in a range of 1.5% to 3.0% of the total amount of the alloy,
• Magnesium, existing in a range of 0.00% to 0.030% of the total amount of the alloy,
• Cerium, existing in a range of 0.005% to 0.030% of the total amount of the alloy,
• Sulfur, existing in a range of less than 0,030% of the total amount of the alloy
• Phosphorus, existing in a range of less than 0.050% of the total amount of the alloy,
• Tin, existing in a range of 0.01% to 0.13% of the total amount of the alloy,
• Copper, existing in a range of 0.2% to 1.3% of the total amount of the alloy, and
• Molybdenum, existing in a range of 0.05% to 0.40% of the total amount of the alloy;
• these levels are balanced so that the Hot Resistance Factor (HRF) is between 0.5 and 1.7%, such factor defined by:
• HRF=3×(% Mo)+1×(% Sn)+0,25×(% Cu)(percentages by weight)
• wherein chromium is absent in the alloy, the matrix of the microstructure of said vermicular cast iron alloy comprises a fine pearlitic matrix comprising pearlite and with graphite particles predominantly in vermicular form and with the presence of graphite nodules in up to 20%, and wherein an average interlamellar spacing of the pearlite is about 0.25 μm.